Improving the documentation about Github Actions so the right branch …

…appears in coveralls

README.md

@@ -175,10 +175,13 @@ test:
  - run: |
  bundle config path vendor/bundle
  bundle install --without=documentation --jobs 4 --retry 3
-
+ - name: Extract branch name
+ shell: bash
+ run: echo "##[set-output name=branch;]$(echo ${GITHUB_REF#refs/heads/})"
+ id: get_branch
  - run: bundle exec slather
  env:
- GIT_BRANCH: ${{ github.event.pull_request.head.ref }}
+ GIT_BRANCH: ${{ steps.get_branch.outputs.branch }}
  CI_PULL_REQUEST: ${{ github.event.number }}
  COVERAGE_ACCESS_TOKEN: ${{ secrets.GITHUB_TOKEN }}