Bump ruby/setup-ruby from 1.238.0 to 1.242.0

Bumps [ruby/setup-ruby](https://github.com/ruby/setup-ruby) from 1.238.0 to 1.242.0.
- [Release notes](https://github.com/ruby/setup-ruby/releases)
- [Changelog](https://github.com/ruby/setup-ruby/blob/master/release.rb)
- [Commits](ruby/setup-ruby@e34163c...cb0fda5)

---
updated-dependencies:
- dependency-name: ruby/setup-ruby
  dependency-version: 1.242.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/cibuild.yaml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v4
-      - uses: ruby/setup-ruby@e34163cd15f4bb403dcd72d98e295997e6a55798 # v1.238.0
+      - uses: ruby/setup-ruby@cb0fda56a307b8c78d38320cd40d9eb22a3bf04e # v1.242.0
         with:
           ruby-version: ${{ matrix.ruby }}
       - name: script/cibuild

.github/workflows/pages-gem.yml

@@ -14,7 +14,7 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
       - name: Setup Ruby
-        uses: ruby/setup-ruby@e34163cd15f4bb403dcd72d98e295997e6a55798 # v1.238.0
+        uses: ruby/setup-ruby@cb0fda56a307b8c78d38320cd40d9eb22a3bf04e # v1.242.0
         with:
           ruby-version: "3.3"
       - name: Build gem