fix codecov upload (closes #381) (#382)

* fix codecov upload (closes #381)

The codecov action can generate a usable report itself, but it needs the
coverage package installed and accessible. This is not the case anymore,
since it's now only installed in the hatch test environment. So we
generate the report ourselves.

* use coverage from hatch env

* Update {{cookiecutter.project_name}}/.github/workflows/test.yaml

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Co-authored-by: Philipp A. <flying-sheep@web.de>
Co-authored-by: Gregor Sturm <mail@gregor-sturm.de>

Author: 3 people

{{cookiecutter.project_name}}/.github/workflows/test.yaml

@@ -55,5 +55,7 @@ jobs:
           PLATFORM: ${{ matrix.os }}
           DISPLAY: :42
         run: uvx hatch test --cover --python ${{ matrix.python }}
+      - name: generate coverage report
+        run: uvx hatch run hatch-test.py${{ matrix.python }}:coverage xml
       - name: Upload coverage
         uses: codecov/codecov-action@v4