Upload coverage report with linux only

.github/workflows/test_pysteps.yml

@@ -20,8 +20,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ "windows-latest" ] # [ "ubuntu-latest", "macos-latest", "windows-latest" ]
-        python-version: [ "3.6" ] #, "3.8" ]
+        os: [ "ubuntu-latest", "macos-latest", "windows-latest" ]
+        python-version: [ "3.6", "3.8" ]
       max-parallel: 6
 
     defaults:
@@ -92,18 +92,16 @@ jobs:
         working-directory: ${{github.workspace}}/pysteps_data
         env:
           PYSTEPSRC: ${{github.workspace}}/pysteps_data/pystepsrc
-        run: |
-          pytest --pyargs pysteps --cov=pysteps --cov-report=xml --cov-report=term -ra
-          mv coverage.xml ${{github.workspace}}
-          ls -l ${{github.workspace}}
+        run: pytest --pyargs pysteps --cov=pysteps --cov-report=xml --cov-report=term -ra
 
-      - name: Upload coverage to Codecov
+      - name: Upload coverage to Codecov (Linux only)
+        if: matrix.os == 'ubuntu-latest'
         uses: codecov/codecov-action@v1
         env:
           OS: ${{ matrix.os }}
           PYTHON: ${{ matrix.python-version }}
         with:
-          file: ./coverage.xml
+          file: ${{github.workspace}}/pysteps_data/coverage.xml
           flags: unit_tests
           env_vars: OS,PYTHON
           fail_ci_if_error: true