Use GitHub actions for testing [wip]

Author: sshaw

.github/workflows/ci.yml

@@ -0,0 +1,30 @@
+name: Ruby
+
+on:
+  - push
+  - pull_request
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        ruby: ['3.2', '3.1', '3.0', '2.7', '2.6', '2.5', '2.4' ]
+        gemfile: [gemfiles/as4.gemfile, gemfiles/as5.gemfile, gemfiles/as6.gemfile]
+        exclude:
+          - ruby-version: 2.3
+            gemfile: gemfiles/as6.gemfile
+          - ruby-version: 2.4
+            gemfile: gemfiles/as6.gemfile
+          - ruby-version: 2.7
+            gemfile: gemfiles/as4.gemfile
+
+    steps:
+      - uses: actions/checkout@v3
+      - uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: ${{ matrix.ruby }}
+          bundler-cache: true
+
+      - run: bundle exec rake