Automatically label PRs to sync by default (#822)

Author: MattyTheHacker

.github/workflows/pr-auto-label.yml

@@ -0,0 +1,26 @@
+name: "Automatically mark PRs to sync"
+
+on:
+  pull_request_target:
+    types:
+      - opened
+
+jobs:
+  labeler:
+    if: github.event.pull_request.user.type != 'Bot'
+    permissions:
+      pull-requests: write
+
+    runs-on: ubuntu-latest
+    steps:
+      - name: Add "sync" label to PR
+        run: gh pr edit "$PR_URL" --add-label sync
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          PR_URL: ${{ github.event.pull_request.html_url }}
+
+      - name: Comment on PR to explain sync label
+        run: gh pr comment "$PR_URL" --body "This pull request has been marked to **automatically sync** to its base branch. You can **disable** this behavior by removing the `sync` label."
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          PR_URL: ${{ github.event.pull_request.html_url }}

.github/workflows/pr-auto-merge.yml

@@ -0,0 +1,23 @@
+name: "Automatically enable auto-merge on PRs"
+
+on:
+  pull_request_target:
+    types:
+      - opened
+      - ready_for_review
+    branches:
+      - main
+
+jobs:
+  enable-automerge:
+    if: github.event.pull_request.draft == false
+    permissions:
+      pull-requests: write
+
+    runs-on: ubuntu-latest
+    steps:
+      - name: Enable auto-merge for the PR
+        run: gh pr merge "$PR_URL" --auto --squash
+        env:
+          GH_TOKEN: ${{ secrets.PR_AUTO_UPDATE_TOKEN }}
+          PR_URL: ${{ github.event.pull_request.html_url }}