swap back to ruby 3.3

Author: thompcd

.github/workflows/ci.yml

@@ -8,7 +8,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: ruby/setup-ruby@v1
         with:
-          ruby-version: 'head'
+          ruby-version: '3.3'
       - name: Install dependencies
         run: bundle add appraisal && bundle install && bundle exec appraisal
       - name: Setup Pages