Bump ruby/setup-ruby from 1.237.0 to 1.268.0

Bumps [ruby/setup-ruby](https://github.com/ruby/setup-ruby) from 1.237.0 to 1.268.0.
- [Release notes](https://github.com/ruby/setup-ruby/releases)
- [Changelog](https://github.com/ruby/setup-ruby/blob/master/release.rb)
- [Commits](ruby/setup-ruby@v1.237.0...8aeb6ff)

---
updated-dependencies:
- dependency-name: ruby/setup-ruby
  dependency-version: 1.268.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

.github/workflows/release_gem.yml

@@ -25,7 +25,7 @@ jobs:
       - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
 
       - name: Set up Ruby
-        uses: ruby/setup-ruby@eaecf785f6a34567a6d97f686bbb7bccc1ac1e5c # v1.237.0
+        uses: ruby/setup-ruby@8aeb6ff8030dd539317f8e1769a044873b56ea71 # v1.268.0
         with:
           bundler-cache: true
           ruby-version: ruby