ci: Update Ruby version due to GitHub Actions error

/opt/hostedtoolcache/Ruby/3.1.4/x64/bin/bundle install --jobs 4
Fetching gem metadata from https://rubygems.org/...........
sass-embedded-1.78.0-x86_64-linux-gnu requires ruby version >= 3.2, which is
incompatible with the current version, 3.1.4
Error: The process '/opt/hostedtoolcache/Ruby/3.1.4/x64/bin/bundle' failed with exit code 5

.github/workflows/jekyll.yml

@@ -36,7 +36,7 @@ jobs:
       - name: Setup Ruby
         uses: ruby/setup-ruby@8575951200e472d5f2d95c625da0c7bec8217c42 # v1.161.0
         with:
-          ruby-version: '3.1' # Not needed with a .ruby-version file
+          ruby-version: '3.3' # Not needed with a .ruby-version file
           bundler-cache: true # runs 'bundle install' and caches installed gems automatically
           cache-version: 0 # Increment this number if you need to re-download cached gems
       - name: Setup Pages