Bump ruby/setup-ruby from 1.307.0 to 1.308.0

Bumps [ruby/setup-ruby](https://github.com/ruby/setup-ruby) from 1.307.0 to 1.308.0.
- [Release notes](https://github.com/ruby/setup-ruby/releases)
- [Changelog](https://github.com/ruby/setup-ruby/blob/master/release.rb)
- [Commits](ruby/setup-ruby@6aaa311...97ecb7b)

---
updated-dependencies:
- dependency-name: ruby/setup-ruby
  dependency-version: 1.308.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -10,7 +10,7 @@ jobs:
     timeout-minutes: 30
     steps:
     - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
-    - uses: ruby/setup-ruby@6aaa311d81eba98ae12eaffbcb63296ace0efcde # v1.307.0
+    - uses: ruby/setup-ruby@97ecb7b512899eb71ab1bf2310a624c6f1589ac6 # v1.308.0
       with:
         bundler-cache: true
         ruby-version: "2.7.2"