Make proto-gen and proto-swagger-gen to use docker

[hallazzang]

Description

Make proto-gen and proto-swagger-gen make command to use docker for deterministic stub generation.
As cosmos/cosmos-sdk#7933 is an ongoing issue, we use slightly modified Dockerfile for our own use and publish it onto Docker Hub(bharvest/liquidity-proto-gen).
Later, it may use updated tendermintdev/sdk-proto-gen image instead.

closes: #192

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• Review Codecov Report in the comment section below once CI passes

[codecov]

Codecov Report

Merging #216 (2415f99) into develop (5c05566) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop     #216   +/-   ##
========================================
  Coverage    83.43%   83.43%           
========================================
  Files           20       20           
  Lines         2349     2349           
========================================
  Hits          1960     1960           
  Misses         209      209           
  Partials       180      180           

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[hallazzang]

As cosmos/cosmos-sdk#9064 merged, we can use tendermintdev/sdk-proto-gen image instead of bharvest/liquidity-proto-gen but in tendermintdev/sdk-proto-gen, grpc gateway version is set to 1.14.7 while we need to use 1.16.0.
Maybe creating new issue in cosmos-sdk will be the solution but for now we will use bharvest/liquidity-proto-gen.
Also note that there's no github workflow that builds and pushes our docker image(all done manually).