Move coveralls to be a separate step (#22)

Author: IvanYashchuk

.github/workflows/ci.yml

@@ -45,11 +45,11 @@ jobs:
 
       - name: Test with pytest
         shell: bash
-        env:
-          COVERALLS_REPO_TOKEN: ${{ secrets.COVERALLS_REPO_TOKEN }}
         run: |
           source /home/firedrake/firedrake/bin/activate
           python -c "import sys; print('\n'.join(sys.path))"
           python -m pytest --cov=firedrake_ts --cov-config=tests/.coveragerc tests/
-          coveralls
           bash <(curl -s https://codecov.io/bash)
+
+      - name: Coveralls
+        uses: coverallsapp/github-action@v2