chore: fix x/reactions events

[RiccardoM]

Description

This PR fixes the x/reactions events types and missing attributes.

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Author Checklist

All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues.

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 #940 (02fa0ba) into master (8adb7c9) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #940   +/-   ##
=======================================
  Coverage   82.76%   82.76%           
=======================================
  Files         166      166           
  Lines       14014    14015    +1     
=======================================
+ Hits        11598    11599    +1     
  Misses       1943     1943           
  Partials      473      473           

Impacted Files	Coverage Δ
x/reactions/keeper/msg_server.go	96.40% <100.00%> (+0.01%)	⬆️

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