Try format option to fix coveralls issues

.github/workflows/build.yaml

@@ -27,7 +27,7 @@ jobs:
       run: |
         python -m pip install --upgrade pip
         pip install -e .[tests]
-        pip install coverage "coveralls<3.3"
+        pip install coverage
     - name: Run tests
       run: | 
         coverage run -m pytest
@@ -38,6 +38,7 @@ jobs:
       uses: coverallsapp/github-action@v2
       with:
         parallel: true
+        format: cobertura
   finish:
     runs-on: ubuntu-latest
     needs: run_tests