Add s3 cleanup

.github/workflows/s3-cleanup.yml

@@ -0,0 +1,27 @@
+name: Delete S3 Files on PR Merged
+
+on:
+  pull_request:
+    types:
+      - closed
+
+jobs:
+  delete-s3-files:
+    if: github.event.pull_request.merged == true
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Set up AWS CLI
+        uses: aws-actions/configure-aws-credentials@v1
+        with:
+          aws-access-key-id: ${{ secrets.AWS_ACCESS_KEY_ID }}
+          aws-secret-access-key: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
+          aws-region: ${{ secrets.AWS_REGION }}
+
+      - name: Remove files from S3
+        run: |
+          PR_NUMBER=${{ github.event.pull_request.number }}
+          aws s3 rm s3://${{ secrets.AWS_S3_BUCKET }}/pr/${PR_NUMBER}/ --recursive