Add support for Ruby 3.3

Author: koppen

.github/workflows/main.yml

@@ -17,6 +17,7 @@ jobs:
           - '3.0'
           - '3.1'
           - '3.2'
+          - '3.3'
 
     steps:
     - uses: actions/checkout@v4
@@ -38,6 +39,6 @@ jobs:
       uses: ruby/setup-ruby@v1
       with:
         bundler-cache: true
-        ruby-version: '3.2'
+        ruby-version: '3.3'
     - name: StandardRB
       run: bundle exec rake standard