merge_comment.yml

name: Add merge comment

on:
  pull_request:
    types: [closed]

permissions:
  contents: read
  pull-requests: write

jobs:
  add-merge-comment:
    runs-on: ubuntu-latest
    if: github.event.pull_request.merged == true
    steps:
    - name: Add comment to merged pull request
      uses: actions/github-script@v6
      with:
        github-token: ${{ secrets.GITHUB_TOKEN }}
        script: |
          const pull_request = context.payload.pull_request;
          const author = pull_request.user.login;
          const issue_number = pull_request.number;
          const body = `Thanks @${author} 🚀`;

          await github.rest.issues.createComment({
            owner: context.repo.owner,
            repo: context.repo.repo,
            issue_number: issue_number,
            body: body
          });