ci(git-changesets): update version from master -> v3

[collin-miller]

Updating git-changesets to use the v3 install instead of the old default branch.

Description

This will resolve the dependency on the legacy default branch. If this or a similar change is not merged the workflows will break.

Related Issue

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Chore (non-breaking change that does not add functionality or fix an issue)

Checklist:

• I have read the CONTRIBUTING document.
• I have run the pre-merge tests locally and they pass.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• If Gemfile.lock has changed, I have used --conservative to do it and included the full output in the Description above.
• All new and existing tests passed.
• All commits have been signed-off for the Developer Certificate of Origin.

[collin-miller]

@Stromweld would you be able to take a look at this?