[ARC-271] Update GitHub action that reports fake test results on PR

    - Update the LouisBrunner/checks-action action to v2.0.0 to use Node 20 and get rid of deprecation warning
    - Make the action work with plugin forks

Author: bigorn0

.github/workflows/fake-pr-tests.yml

@@ -0,0 +1,18 @@
+name: PR tests
+on:
+  pull_request:
+    types: [auto_merge_enabled]
+  workflow_dispatch:
+
+jobs:
+  skip:
+    name: Report fake success for PR tests
+    runs-on: ubuntu-latest
+    permissions:
+      checks: write
+    steps:
+      - uses: LouisBrunner/checks-action@v2.0.0
+        with:
+          name: Run PR tests (Plugins)
+          conclusion: success
+          token: ${{ secrets.GITHUB_TOKEN }}