CI: add Ruby 3.1, 3.2, and 3.3 to the test matrix

.github/workflows/ci.yml

@@ -1,23 +1,18 @@
 name: CI
-
 on: [push, pull_request]
-
 jobs:
   test:
     strategy:
       fail-fast: false
       matrix:
-        ruby: ['2.5', '2.6', '2.7', '3.0']
+        ruby: ['2.5', '2.6', '2.7', '3.0', '3.1', '3.2', '3.3']
     runs-on: ubuntu-latest
-
     steps:
     - name: Checkout
-      uses: actions/checkout@v2
+      uses: actions/checkout@v4
     - name: Set up Ruby
       uses: ruby/setup-ruby@v1
       with:
         ruby-version: ${{ matrix.ruby }}
-    - name: Install dependencies
-      run: bundle install
-    - name: Run tests
-      run: bundle exec rake
+        bundler-cache: true
+    - run: bundle exec rake