Bump ruby/setup-ruby from 1.174.0 to 1.175.0

Bumps [ruby/setup-ruby](https://github.com/ruby/setup-ruby) from 1.174.0 to 1.175.0.
- [Release notes](https://github.com/ruby/setup-ruby/releases)
- [Commits](ruby/setup-ruby@6bd3d99...70da3bb)

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

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

.github/workflows/gh-pages.yml

@@ -28,7 +28,7 @@ jobs:
         with:
           fetch-depth: 0 # need full history to get page last modified times
       - name: Setup Ruby
-        uses: ruby/setup-ruby@6bd3d993c602f6b675728ebaecb2b569ff86e99b # v1.174.0
+        uses: ruby/setup-ruby@70da3bbf44ac06db1b0547ce2acc9380a5270d1e # v1.175.0
         with:
           ruby-version: '3.1'
           bundler-cache: true # runs 'bundle install' and caches installed gems automatically