chore: Add feature branch deployments

.github/workflows/deploy.yml

@@ -1,9 +1,7 @@
 name: Deploy to staging
 
 on:
-  push:
-    branches:
-      - main
+  pull_request:
 
 jobs:
   deploy:
@@ -18,6 +16,18 @@ jobs:
         with:
           access_token: ${{ github.token }}
 
+      # Post a PR comment before deploying
+      - name: Post a comment while building
+        if: github.event.number
+        uses: mshick/add-pr-comment@v2
+        with:
+          message-id: praul
+          message: |
+            ## Branch preview
+            ⏳ Deploying a preview site...
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
+          repo-token-user-login: 'github-actions[bot]'
+
       - uses: actions/checkout@v3
 
       - uses: pnpm/action-setup@v2
@@ -46,3 +56,32 @@ jobs:
         env:
           BUCKET: s3://${{ secrets.AWS_STAGING_BUCKET_NAME }}/current
         run: bash ./.github/scripts/s3_upload.sh
+
+      # Extract branch name
+      - name: Extract branch name
+        shell: bash
+        ## Allow only alphanumeric characters and convert to lower case,
+        run: echo "branch=$(echo $GITHUB_HEAD_REF | sed 's/[^a-z0-9]/_/ig' | sed 's/[A-Z]/\L&/g')" >> $GITHUB_OUTPUT
+        id: extract_branch
+
+      # Deploy to S3
+      - name: Deploy PR branch
+        if: github.event.number
+        env:
+          BUCKET: s3://${{ secrets.AWS_REVIEW_BUCKET_NAME }}/docs/${{ steps.extract_branch.outputs.branch }}
+        run: bash ./.github/scripts/s3_upload.sh
+
+      # Comment with the deployment link
+      - name: Post an epic deployment link in the PR
+        if: always() && github.event.number
+        uses: mshick/add-pr-comment@v2
+        with:
+          message-id: praul
+          message: |
+            ## Branch preview
+            ✅ Deployed successfully in branch deployment:
+
+            https://${{ steps.extract_branch.outputs.branch }}--docs.review.5afe.dev
+          message-failure: |
+            ## Branch preview
+            ❌ Deploy failed!