ci: add example build to ci

.github/workflows/on-pull-request.yml

@@ -50,3 +50,37 @@ jobs:
 
     - name: Run tests vs redis
       run: make test-redis
+
+  build-examples:
+    runs-on: ubuntu-latest
+    env:
+      MOMENTO_API_KEY: ${{ secrets.ALPHA_TEST_AUTH_TOKEN }}
+
+    steps:
+      - name: Checkout project
+        uses: actions/checkout@v3
+
+      - name: Set up JDK 17
+        uses: actions/setup-java@v3
+        with:
+          java-version: 17
+          distribution: 'corretto'
+
+      - name: Build examples
+        uses: gradle/gradle-build-action@v2
+        id: validation
+        continue-on-error: true
+        with:
+          build-root-directory: ./examples
+          arguments: clean build
+
+      - name: Send CI failure mail
+        if: ${{ steps.validation.outcome == 'failure' }}
+        uses: momentohq/standards-and-practices/github-actions/error-email-action@gh-actions-v1
+        with:
+          username: ${{secrets.MOMENTO_ROBOT_GMAIL_USERNAME}}
+          password: ${{secrets.MOMENTO_ROBOT_GMAIL_PASSWORD}}
+
+      - name: Flag Job Failure
+        if: ${{ steps.validation.outcome == 'failure' }}
+        run: exit 1