Add tests CI matrix with Ruby 3.3 only for now

.github/workflows/ci.yml

@@ -0,0 +1,26 @@
+name: Tests
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        ruby:
+          - '3.3'
+    name: Ruby ${{ matrix.ruby }}
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: ${{ matrix.ruby }}
+          bundler-cache: true # runs 'bundle install' and caches installed gems automatically
+      - name: Run Tests
+        env:
+          RUBYOPT: "-W:deprecated"
+        run: bundle exec rake test