Added GitHub Action

.github/workflows/ci.yml

@@ -0,0 +1,31 @@
+name: Continuous Integration
+
+on: [push, pull_request]
+
+jobs:
+  build:
+    name: Build
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+        with:
+          ref: ${{github.head_ref}}
+
+      - name: Ruby Setup
+        uses: ruby/setup-ruby@v1
+        with:
+          bundler-cache: true
+
+      - name: Environment
+        run: printenv | sort
+
+      - name: Git Setup
+        run: |
+          git config --global init.defaultBranch main
+          git fetch --depth=1 origin "$GITHUB_REF_NAME"
+          git log --pretty=format:"%h %s" main..ci
+
+      - name: Build
+        run: bundle exec rake