feat: Add group module grpc-gateway

[amaury1093]

Description

Closes: #10661

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Author Checklist

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I have...

• included the correct type prefix in the PR title
• added ! to the type prefix if API or client breaking change
• targeted the correct branch (see PR Targeting)
• provided a link to the relevant issue or specification
• followed the guidelines for building modules
• included the necessary unit and integration tests
• added a changelog entry to CHANGELOG.md
• included comments for documenting Go code
• updated the relevant documentation or specification
• reviewed "Files changed" and left comments if necessary
• confirmed all CI checks have passed

Reviewers Checklist

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your handle next to the items reviewed if you only reviewed selected items.

I have...

• confirmed the correct type prefix 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)

[codecov]

Codecov Report

Merging #10773 (a931abc) into master (109bc94) will increase coverage by 0.12%.
The diff coverage is n/a.

❗ Current head a931abc differs from pull request most recent head b3deb34. Consider uploading reports for the commit b3deb34 to get more accurate results

@@            Coverage Diff             @@
##           master   #10773      +/-   ##
==========================================
+ Coverage   64.75%   64.87%   +0.12%     
==========================================
  Files         624      623       -1     
  Lines       60354    60371      +17     
==========================================
+ Hits        39083    39168      +85     
+ Misses      19037    18953      -84     
- Partials     2234     2250      +16     

Impacted Files	Coverage Δ
x/staking/migrations/v045/store.go	50.00% <0.00%> (-50.00%)	⬇️
baseapp/options.go	61.11% <0.00%> (-0.93%)	⬇️
baseapp/abci.go	60.21% <0.00%> (-0.69%)	⬇️
store/types/store.go	64.70% <0.00%> (ø)
x/staking/keeper/delegation.go	72.66% <0.00%> (ø)
store/v2/multi/sub_store.go
store/v2/dbadapter/store.go
db/memdb/db.go
db/adapter.go
db/prefix/prefix.go
... and 32 more

[blushi]

Could you resolve the conflicts?

[atheeshp]

lgtm!

[amaury1093]

When I run go mod tidy in x/group, I have:

go mod tidy
go: downloading github.com/spf13/cobra v1.3.0
go mod tidy: error loading go 1.16 module graph: github.com/cosmos/[email protected] requires
	github.com/cosmos/cosmos-sdk/x/[email protected]: invalid version: unknown revision 000000000000

If reproducibility with go 1.16 is not needed:
	go mod tidy -compat=1.17
For other options, see:
	https://golang.org/doc/modules/pruning

It's weird it's still mentioning 0.44.0