refactor: move legacy gov to v1beta1 (cosmos#10748)

Ref: cosmos#9810

Moves all legacy gov code to `v1beta1`. This preserves all existing behavior (i.e. everything still uses v1beta1). It's merely moving things around to get everything in the right place logistically (hence the large diff still)

---

### Author Checklist

*All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues.*

I have...

- [ ] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
- [ ] targeted the correct branch (see [PR Targeting](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#pr-targeting))
- [ ] provided a link to the relevant issue or specification
- [ ] followed the guidelines for [building modules](https://github.com/cosmos/cosmos-sdk/blob/master/docs/building-modules)
- [ ] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] included comments for [documenting Go code](https://blog.golang.org/godoc)
- [ ] updated the relevant documentation or specification
- [ ] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

*All items are required. Please add a note if the item is not applicable and please add
your handle next to the items reviewed if you only reviewed selected items.*

I have...

- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed 
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

app.go

@@ -66,6 +66,7 @@ import (
 	"github.com/cosmos/cosmos-sdk/x/gov"
 	govkeeper "github.com/cosmos/cosmos-sdk/x/gov/keeper"
 	govtypes "github.com/cosmos/cosmos-sdk/x/gov/types"
+	oldgovtypes "github.com/cosmos/cosmos-sdk/x/gov/types/v1beta1"
 	"github.com/cosmos/cosmos-sdk/x/group"
 	groupkeeper "github.com/cosmos/cosmos-sdk/x/group/keeper"
 	groupmodule "github.com/cosmos/cosmos-sdk/x/group/module"
@@ -295,8 +296,8 @@ func NewSimApp(
 	app.GroupKeeper = groupkeeper.NewKeeper(keys[group.StoreKey], appCodec, app.msgSvcRouter, app.AccountKeeper)
 
 	// register the proposal types
-	govRouter := govtypes.NewRouter()
-	govRouter.AddRoute(govtypes.RouterKey, govtypes.ProposalHandler).
+	govRouter := oldgovtypes.NewRouter()
+	govRouter.AddRoute(govtypes.RouterKey, oldgovtypes.ProposalHandler).
 		AddRoute(paramproposal.RouterKey, params.NewParamChangeProposalHandler(app.ParamsKeeper)).
 		AddRoute(distrtypes.RouterKey, distr.NewCommunityPoolSpendProposalHandler(app.DistrKeeper)).
 		AddRoute(upgradetypes.RouterKey, upgrade.NewSoftwareUpgradeProposalHandler(app.UpgradeKeeper))
@@ -615,7 +616,7 @@ func initParamsKeeper(appCodec codec.BinaryCodec, legacyAmino *codec.LegacyAmino
 	paramsKeeper.Subspace(minttypes.ModuleName)
 	paramsKeeper.Subspace(distrtypes.ModuleName)
 	paramsKeeper.Subspace(slashingtypes.ModuleName)
-	paramsKeeper.Subspace(govtypes.ModuleName).WithKeyTable(govtypes.ParamKeyTable())
+	paramsKeeper.Subspace(govtypes.ModuleName).WithKeyTable(oldgovtypes.ParamKeyTable())
 	paramsKeeper.Subspace(crisistypes.ModuleName)
 
 	return paramsKeeper