chore: add automerge workflow to this repo

.github/workflows/automerge.yml

@@ -0,0 +1,24 @@
+name: automerge
+on:
+  pull_request_target:
+    types:
+      - opened
+      - labeled
+      - ready_for_review
+      - reopened
+      - synchronize
+concurrency: ${{ github.workflow }}-${{ github.ref }}
+jobs:
+  automerge:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    if: contains(github.event.pull_request.labels.*.name, 'automerge') && github.event.pull_request.draft == false
+    steps:
+      - name: Checkout
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
+      - name: Turn on automerge for this PR by a trusted user or bot
+        if: github.event.pull_request.user.login == 'team-tf-cdk' || contains(fromJSON('["OWNER", "MEMBER", "COLLABORATOR"]'), github.event.pull_request.author_association) || github.actor == 'dependabot[bot]'
+        env:
+          GH_TOKEN: ${{ secrets.GH_COMMENT_TOKEN }}
+        run: gh pr merge --auto --squash ${{ github.event.pull_request.number }