ci: switch to Github Actions

.github/workflows/rubygems.yml

@@ -0,0 +1,32 @@
+name: Ruby Gem
+
+on:
+  push:
+    branches: [ "main" ]
+    tags:
+      - 'v*'
+  pull_request:
+    branches: [ "main" ]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        ruby-version: ['2.6', '2.7', '3.0', '3.1']
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Ruby ${{ matrix.ruby-version }}
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: ${{ matrix.ruby-version }}
+          bundler-cache: true
+
+      - name: Run tests
+        run: bundle exec rake
+
+      - uses: paambaati/codeclimate-action@v9.0.0
+        env:
+          CC_TEST_REPORTER_ID: "${{ secrets.CC_TEST_REPORTER_ID }}"