feat: add cli for MsgPruneAcknowledgements

[damiannolan]

Description

• Added CLI for submitting MsgPruneAcknowledgements

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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.
• Re-reviewed Files changed in the Github PR explorer.
• Review Codecov Report in the comment section below once CI passes.

[DimitrisJim]

lgtm, one minor q about the long desc

[damiannolan]

lgtm, one minor q about the long desc

I don't think your question was published in the review by the looks of thiings! 👀

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (26fd1e0) 81.09% compared to head (fbcd7d3) 81.27%.
Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5482      +/-   ##
==========================================
+ Coverage   81.09%   81.27%   +0.18%     
==========================================
  Files         197      197              
  Lines       15234    15234              
==========================================
+ Hits        12354    12382      +28     
+ Misses       2412     2391      -21     
+ Partials      468      461       -7     

see 1 file with indirect coverage changes