fix(gov): don't export deprecated params

[julienrbrt]

Description

ref: #14358, #14093 (comment)

Checked migrate genesis that works properly from a 0.46 genesis vs 0.47 genesis.

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Author Checklist

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• 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
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• confirmed the correct type prefix in the PR title
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• reviewed state machine logic
• reviewed API design and naming
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• reviewed tests and test coverage
• manually tested (if applicable)

[sonarcloud]

[Cosmos SDK] Kudos, SonarCloud Quality Gate passed!   

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0 Code Smells

No Coverage information
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[alexanderbez]

Thanks @julienrbrt!