fix: fetch a failed proposal tally from proposal.FinalTallyResult in the gprc query

[170210]

Description

The TallyResult() is used to fetch the tally result from a proposal, in which the case when a proposal fails does not provide the correct information as this case has been branched into the default case.
This pr cherry-pick the following pr:

• fix(x/gov): grpc query tally for failed proposal cosmos/cosmos-sdk#19725

Motivation and context

How has this been tested?

Screenshots (if appropriate):

Checklist:

• I followed the contributing guidelines and code of conduct.
• I have added a relevant changelog to CHANGELOG.md
• I have added tests to cover my changes.
• I have updated the documentation accordingly.
• I have updated API documentation client/docs/swagger-ui/swagger.yaml

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✅ 170210
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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 70.43%. Comparing base (1038a39) to head (39d1651).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1304   +/-   ##
=======================================
  Coverage   70.42%   70.43%           
=======================================
  Files         643      643           
  Lines       54730    54730           
=======================================
+ Hits        38546    38547    +1     
+ Misses      14011    14010    -1     
  Partials     2173     2173           

Files	Coverage Δ
x/gov/keeper/grpc_query.go	76.38% <100.00%> (ø)

... and 1 file with indirect coverage changes