Create auto-update-pr action

This action keeps PRs up to date when `main` gets pushed to

Author: beqqrry-aws

.github/workflows/auto-update-pr

@@ -0,0 +1,13 @@
+name: "Keep PRs Updated from Main"
+on:
+  push:
+    branches:
+      - main
+jobs:
+  autoupdate:
+    name: Auto Update PR
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: docker://chinthakagodawita/autoupdate-action:v1
+        env:
+          GITHUB_TOKEN: '${{ secrets.GITHUB_TOKEN }}'