Add github token for coveralls

.github/workflows/pythonapp.yml

@@ -34,6 +34,7 @@ jobs:
       id: extract_branch
     - name: Upload coverage
       env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           COVERALLS_REPO_TOKEN: ${{ secrets.COVERALLS_REPO_TOKEN }}
           # This will only work if we also send a "done" event after the
           # whole job is finished.