Consistently generate build tags metadata (#4582)

Dockerfile receives a minor tweak for proper output.

BuildTags value is expected as a plain `netgo,ledger,muslc` string,
however the current approach wraps quotes inside of quotes, and the
resulting string is `'netgo,ledger,muslc'` which gets escaped a
few more times (unnecessarily).

Additionally, Makefile receives a minor tweak for everyone who
builds directly.

With Make 4.3+, the empty whitespace does not seem to work as
originally intended. This causes build tags to be `netgo ledger,`
on Ubuntu 22.04 and other systems that include the newer Make
version. The build tags were intended as `netgo,ledger` which
can be observed on Make 4.2 (shipped with Ubuntu 20.04).

This change swaps out the `+=` use in favor of an explicit `:=`.
Ref: https://www.gnu.org/software/make/manual/html_node/Appending.html

Upstream: cosmos/gaia@297cdb9
(cherry picked from commit 9d01b70)

CHANGELOG.md

@@ -40,6 +40,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+
+### Misc Improvements
+
+  * [#4582](https://github.com/osmosis-labs/osmosis/pull/4582) Consistently generate build tags metadata, to return a comma-separated list without stray quotes. This affects the output from `version` CLI subcommand and server info API calls.
+
 ## v15.0.0
 
 This release containts the following new modules:

Dockerfile

@@ -46,7 +46,7 @@ RUN --mount=type=cache,target=/root/.cache/go-build \
             -X github.com/cosmos/cosmos-sdk/version.AppName="osmosisd" \
             -X github.com/cosmos/cosmos-sdk/version.Version=${GIT_VERSION} \
             -X github.com/cosmos/cosmos-sdk/version.Commit=${GIT_COMMIT} \
-            -X github.com/cosmos/cosmos-sdk/version.BuildTags='netgo,ledger,muslc' \
+            -X github.com/cosmos/cosmos-sdk/version.BuildTags=netgo,ledger,muslc \
             -w -s -linkmode=external -extldflags '-Wl,-z,muldefs -static'" \
         -trimpath \
         -o /osmosis/build/osmosisd \

Makefile

@@ -50,7 +50,7 @@ build_tags += $(BUILD_TAGS)
 build_tags := $(strip $(build_tags))
 
 whitespace :=
-whitespace += $(whitespace)
+whitespace := $(whitespace) $(whitespace)
 comma := ,
 build_tags_comma_sep := $(subst $(whitespace),$(comma),$(build_tags))