feat(x/ecocredit): add batch denom to event bridge

[ryanchristo]

Description

This pull request adds batch_denom to EventBridge to make verification easier on the bridge service.

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Author Checklist

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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 #1837 (a8b04c6) into main (7673be6) will increase coverage by 0.00%.
The diff coverage is 100.00%.

❗ Current head a8b04c6 differs from pull request most recent head 0b86057. Consider uploading reports for the commit 0b86057 to get more accurate results

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1837   +/-   ##
=======================================
  Coverage   73.01%   73.01%           
=======================================
  Files         228      228           
  Lines       13581    13582    +1     
=======================================
+ Hits         9916     9917    +1     
  Misses       2934     2934           
  Partials      731      731           

Impacted Files	Coverage Δ
x/ecocredit/base/keeper/msg_bridge.go	69.04% <100.00%> (+0.75%)	⬆️