ci: recreate dependabot PR on develop (italia#408)

Author: valeriocomo

.github/workflows/dependabot-on-develop.yml

@@ -0,0 +1,57 @@
+name: Recreate Dependabot PR on develop
+
+on:
+  pull_request:
+    types: [opened]
+    branches:
+      - main
+
+jobs:
+  rebase-dependabot-to-develop:
+    if: github.actor == 'dependabot[bot]' || github.actor == 'dependabot-preview[bot]'
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Setup Git
+        run: |
+          git config user.name "github-actions[bot]"
+          git config user.email "github-actions[bot]@users.noreply.github.com"
+
+      - name: Fetch full history and all branches
+        run: git fetch --unshallow --all
+
+      - name: Create a new branch from develop with dependabot changes
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          ORIGINAL_BRANCH="${{ github.event.pull_request.head.ref }}"
+          NEW_BRANCH="dependabot-develop-${ORIGINAL_BRANCH}"
+
+          # Create new branch based on develop
+          git checkout origin/develop -b $NEW_BRANCH
+
+          # Get last commit message from original Dependabot branch
+          LAST_COMMIT_MSG=$(git log -1 --pretty=%B origin/$ORIGINAL_BRANCH)
+
+          # Merge Dependabot changes into the new branch
+          git merge --no-commit origin/$ORIGINAL_BRANCH || true
+          git commit -m "$LAST_COMMIT_MSG"
+          git push origin $NEW_BRANCH
+
+          # Create new pull request against develop
+          gh pr create \
+            --base develop \
+            --head $NEW_BRANCH \
+            --title "${{ github.event.pull_request.title }} (rebased onto develop)" \
+            --body "This is an automated copy of #${{ github.event.pull_request.number }}, targeting \`develop\` instead of \`main\`."
+
+          # Close the original PR
+          gh pr close ${{ github.event.pull_request.number }} --comment "Automatically closed: a new PR has been created against \`develop\`."
+
+          # Delete the original Dependabot branch
+          gh api \
+            -X DELETE \
+            repos/${{ github.repository }}/git/refs/heads/$ORIGINAL_BRANCH