chore: remove unnecessary arg from RelayPacket testing function (#813)

## Description



closes: #XXXX

---

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- [ ] Targeted PR against correct branch (see [CONTRIBUTING.md](https://github.com/cosmos/ibc-go/blob/master/CONTRIBUTING.md#pr-targeting))
- [ ] Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
- [ ] Code follows the [module structure standards](https://github.com/cosmos/cosmos-sdk/blob/master/docs/building-modules/structure.md).
- [ ] Wrote unit and integration [tests](https://github.com/cosmos/ibc-go/blob/master/CONTRIBUTING.md#testing)
- [ ] Updated relevant documentation (`docs/`) or specification (`x/<module>/spec/`)
- [ ] Added relevant `godoc` [comments](https://blog.golang.org/godoc-documenting-go-code).
- [ ] Added a relevant changelog entry to the `Unreleased` section in `CHANGELOG.md`
- [ ] Re-reviewed `Files changed` in the Github PR explorer
- [ ] Review `Codecov Report` in the comment section below once CI passes

CHANGELOG.md

@@ -43,6 +43,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ### API Breaking
 
+* (testing( [\#813](https://github.com/cosmos/ibc-go/pull/813) The `ack` argument to the testing function `RelayPacket` has been removed as it is no longer needed.
 * (testing) [\#774](https://github.com/cosmos/ibc-go/pull/774) Added `ChainID` arg to `SetupWithGenesisValSet` on the testing app. `Coordinator` generated ChainIDs now starts at index 1
 * (transfer) [\#675](https://github.com/cosmos/ibc-go/pull/675) Transfer `NewKeeper` now takes in an ICS4Wrapper. The ICS4Wrapper may be the IBC Channel Keeper when ICS20 is not used in a middleware stack. The ICS4Wrapper is required for applications wishing to connect middleware to ICS20.
 * (core) [\#650](https://github.com/cosmos/ibc-go/pull/650) Modify `OnChanOpenTry` IBC application module callback to return the negotiated app version. The version passed into the `MsgChanOpenTry` has been deprecated and will be ignored by core IBC.

modules/apps/27-interchain-accounts/host/ibc_module_test.go

@@ -647,8 +647,7 @@ func (suite *InterchainAccountsTestSuite) TestControlAccountAfterChannelClose()
 
 	// relay the packet
 	packetRelay := channeltypes.NewPacket(icaPacketData.GetBytes(), 1, path.EndpointA.ChannelConfig.PortID, path.EndpointA.ChannelID, path.EndpointB.ChannelConfig.PortID, path.EndpointB.ChannelID, clienttypes.ZeroHeight(), ^uint64(0))
-	ack := channeltypes.NewResultAcknowledgement([]byte{byte(1)})
-	err = path.RelayPacket(packetRelay, ack.Acknowledgement())
+	err = path.RelayPacket(packetRelay)
 	suite.Require().NoError(err) // relay committed
 
 	// check that the ica balance is updated
@@ -679,8 +678,7 @@ func (suite *InterchainAccountsTestSuite) TestControlAccountAfterChannelClose()
 
 	// relay the packet
 	packetRelay = channeltypes.NewPacket(icaPacketData.GetBytes(), 1, path.EndpointA.ChannelConfig.PortID, path.EndpointA.ChannelID, path.EndpointB.ChannelConfig.PortID, path.EndpointB.ChannelID, clienttypes.ZeroHeight(), ^uint64(0))
-	ack = channeltypes.NewResultAcknowledgement([]byte{byte(1)})
-	err = path.RelayPacket(packetRelay, ack.Acknowledgement())
+	err = path.RelayPacket(packetRelay)
 	suite.Require().NoError(err) // relay committed
 
 	// check that the ica balance is updated

modules/apps/transfer/keeper/relay_test.go

@@ -192,8 +192,7 @@ func (suite *KeeperTestSuite) TestOnRecvPacket() {
 				// relay send packet
 				fungibleTokenPacket := types.NewFungibleTokenPacketData(coinFromBToA.Denom, coinFromBToA.Amount.String(), suite.chainB.SenderAccount.GetAddress().String(), suite.chainA.SenderAccount.GetAddress().String())
 				packet := channeltypes.NewPacket(fungibleTokenPacket.GetBytes(), 1, path.EndpointB.ChannelConfig.PortID, path.EndpointB.ChannelID, path.EndpointA.ChannelConfig.PortID, path.EndpointA.ChannelID, clienttypes.NewHeight(0, 110), 0)
-				ack := channeltypes.NewResultAcknowledgement([]byte{byte(1)})
-				err = path.RelayPacket(packet, ack.Acknowledgement())
+				err = path.RelayPacket(packet)
 				suite.Require().NoError(err) // relay committed
 
 				seq++

modules/apps/transfer/transfer_test.go

@@ -63,8 +63,7 @@ func (suite *TransferTestSuite) TestHandleMsgTransfer() {
 	// relay send
 	fungibleTokenPacket := types.NewFungibleTokenPacketData(coinToSendToB.Denom, coinToSendToB.Amount.String(), suite.chainA.SenderAccount.GetAddress().String(), suite.chainB.SenderAccount.GetAddress().String())
 	packet := channeltypes.NewPacket(fungibleTokenPacket.GetBytes(), 1, path.EndpointA.ChannelConfig.PortID, path.EndpointA.ChannelID, path.EndpointB.ChannelConfig.PortID, path.EndpointB.ChannelID, timeoutHeight, 0)
-	ack := channeltypes.NewResultAcknowledgement([]byte{byte(1)})
-	err = path.RelayPacket(packet, ack.Acknowledgement())
+	err = path.RelayPacket(packet)
 	suite.Require().NoError(err) // relay committed
 
 	// check that voucher exists on chain B
@@ -92,7 +91,7 @@ func (suite *TransferTestSuite) TestHandleMsgTransfer() {
 	fullDenomPath := types.GetPrefixedDenom(pathBtoC.EndpointB.ChannelConfig.PortID, pathBtoC.EndpointB.ChannelID, voucherDenomTrace.GetFullDenomPath())
 	fungibleTokenPacket = types.NewFungibleTokenPacketData(voucherDenomTrace.GetFullDenomPath(), coinSentFromAToB.Amount.String(), suite.chainB.SenderAccount.GetAddress().String(), suite.chainC.SenderAccount.GetAddress().String())
 	packet = channeltypes.NewPacket(fungibleTokenPacket.GetBytes(), 1, pathBtoC.EndpointA.ChannelConfig.PortID, pathBtoC.EndpointA.ChannelID, pathBtoC.EndpointB.ChannelConfig.PortID, pathBtoC.EndpointB.ChannelID, timeoutHeight, 0)
-	err = pathBtoC.RelayPacket(packet, ack.Acknowledgement())
+	err = pathBtoC.RelayPacket(packet)
 	suite.Require().NoError(err) // relay committed
 
 	coinSentFromBToC := sdk.NewCoin(types.ParseDenomTrace(fullDenomPath).IBCDenom(), amount)
@@ -115,7 +114,7 @@ func (suite *TransferTestSuite) TestHandleMsgTransfer() {
 	// NOTE: fungible token is prefixed with the full trace in order to verify the packet commitment
 	fungibleTokenPacket = types.NewFungibleTokenPacketData(fullDenomPath, coinSentFromBToC.Amount.String(), suite.chainC.SenderAccount.GetAddress().String(), suite.chainB.SenderAccount.GetAddress().String())
 	packet = channeltypes.NewPacket(fungibleTokenPacket.GetBytes(), 1, pathBtoC.EndpointB.ChannelConfig.PortID, pathBtoC.EndpointB.ChannelID, pathBtoC.EndpointA.ChannelConfig.PortID, pathBtoC.EndpointA.ChannelID, timeoutHeight, 0)
-	err = pathBtoC.RelayPacket(packet, ack.Acknowledgement())
+	err = pathBtoC.RelayPacket(packet)
 	suite.Require().NoError(err) // relay committed
 
 	balance = suite.chainB.GetSimApp().BankKeeper.GetBalance(suite.chainB.GetContext(), suite.chainB.SenderAccount.GetAddress(), coinSentFromAToB.Denom)

testing/path.go

@@ -38,7 +38,7 @@ func (path *Path) SetChannelOrdered() {
 // RelayPacket attempts to relay the packet first on EndpointA and then on EndpointB
 // if EndpointA does not contain a packet commitment for that packet. An error is returned
 // if a relay step fails or the packet commitment does not exist on either endpoint.
-func (path *Path) RelayPacket(packet channeltypes.Packet, _ []byte) error {
+func (path *Path) RelayPacket(packet channeltypes.Packet) error {
 	pc := path.EndpointA.Chain.App.GetIBCKeeper().ChannelKeeper.GetPacketCommitment(path.EndpointA.Chain.GetContext(), packet.GetSourcePort(), packet.GetSourceChannel(), packet.GetSequence())
 	if bytes.Equal(pc, channeltypes.CommitPacket(path.EndpointA.Chain.App.AppCodec(), packet)) {