Add workflow that deploys to staging

.github/workflows/deploy.yml

@@ -0,0 +1,26 @@
+name: Deploy to staging
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  deploy:
+    name: Deploy to staging
+    runs-on: ubuntu-latest
+    steps:
+      - name: Wait for tests to succeed
+        uses: lewagon/wait-on-check-action@v1.0.0
+        with:
+          ref: ${{ github.ref }}
+          running-workflow-name: Deploy to staging
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
+          wait-interval: 10
+      - name: git-checkout
+        uses: actions/checkout@v2
+      - name: Push
+        uses: ad-m/github-push-action@master
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          branch: staging
+          force: true