chore: bump ruby/setup-ruby from 1.218.0 to 1.221.0

Bumps [ruby/setup-ruby](https://github.com/ruby/setup-ruby) from 1.218.0 to 1.221.0.
- [Release notes](https://github.com/ruby/setup-ruby/releases)
- [Changelog](https://github.com/ruby/setup-ruby/blob/master/release.rb)
- [Commits](ruby/setup-ruby@d781c1b...32110d4)

---
updated-dependencies:
- dependency-name: ruby/setup-ruby
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

Diff for: .github/workflows/citation-validation.yml

@@ -44,7 +44,7 @@ jobs:
         uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683  # v4.2.2
 
       - name: Setup Ruby ${{ needs.get-ruby-version.outputs.version }}
-        uses: ruby/setup-ruby@d781c1b4ed31764801bfae177617bb0446f5ef8d  # v1.218.0
+        uses: ruby/setup-ruby@32110d4e311bd8996b2a82bf2a43b714ccc91777  # v1.221.0
         with:
           ruby-version: ${{ needs.get-ruby-version.outputs.version }}
 

Diff for: .github/workflows/document-validation.yml

@@ -58,7 +58,7 @@ jobs:
         uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683  # v4.2.2
 
       - name: Setup Ruby ${{ needs.get-ruby-version.outputs.version }}
-        uses: ruby/setup-ruby@d781c1b4ed31764801bfae177617bb0446f5ef8d # v1.218.0
+        uses: ruby/setup-ruby@32110d4e311bd8996b2a82bf2a43b714ccc91777 # v1.221.0
         with:
           ruby-version: ${{ needs.get-ruby-version.outputs.version }}