message: fix abidiff action baseline ref
diff: @@ -37,7 +37,7 @@ jobs:
  uses: actions/checkout@v2
  with:
  path: old
  - ref: develop
  + ref: ${{ github.event.pull_request.base.ref }}
  - name: Install abidiff
  run: sudo apt-get install abigail-tools
  - name: Build both libraries
  