docs: update x/types/v1/gov.pb.go README.md links to v0.50

[MozirDmitriy]

Description

Updates links in x/types/v1/gov.pb.go from v0.47 to v0.50 to reflect the latest maintained version of the SDK. This change ensures that users are directed to the most up-to-date documentation and code references.

Closes: #XXXX

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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
• confirmed ! in the type prefix if API or client breaking change (not needed for docs changes)
• targeted the correct branch (see PR Targeting)
• provided a link to the relevant issue or specification
• reviewed "Files changed" and left comments if necessary
• included the necessary unit and integration tests (not needed for docs changes)
• added a changelog entry to CHANGELOG.md:
• updated the relevant documentation or specification
• confirmed all CI checks have passed

Reviewers Checklist

All items are required. Please add a note if the item is not applicable and please add
your handle next to the items reviewed if you only reviewed selected items.

Please see Pull Request Reviewer section in the contributing guide for more information on how to review a pull request.

I have...

• confirmed the correct type prefix in the PR title
• confirmed all author checklist items have been addressed
• reviewed state machine logic, API design and naming, documentation is accurate, tests and test coverage