test: added tests for UpdateChannelParams

[MukulKolpe]

Description

Added tests for UpdateChannelParams in msg_server_test.go.

closes: #5479

Commit Message / Changelog Entry

test: added tests for `UpdateChannelParams`

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• Targeted PR against the correct branch (see CONTRIBUTING.md).
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
• Code follows the module structure standards and Go style guide.
• Wrote unit and integration tests.
• Updated relevant documentation (docs/) or specification (x/<module>/spec/).
• Added relevant godoc comments.
• Provide a commit message to be used for the changelog entry in the PR description for review.
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[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (7c2996a) 80.88% compared to head (47e7163) 80.94%.
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5494      +/-   ##
==========================================
+ Coverage   80.88%   80.94%   +0.05%     
==========================================
  Files         197      197              
  Lines       15221    15221              
==========================================
+ Hits        12312    12320       +8     
+ Misses       2437     2429       -8     
  Partials      472      472              

see 1 file with indirect coverage changes

[DimitrisJim]

thanks! lgtm!

[crodriguezvega]

Looks great. Thanks, @MukulKolpe.