workflow.yml

name: Check for changes in .github/workflows

on:
  pull_request:
    branches: ["main"]

jobs:
  check:
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v2
      - run: |
          git fetch --no-tags --prune --depth=1 origin +refs/heads/*:refs/remotes/origin/*
      - run: git diff --name-only origin/main HEAD | grep -q ".github/workflows" && echo ".github/workflows has been modified, exiting" && exit 1 || echo ".github/workflows has not been modified"