update python-tests.yml

.github/workflows/python-tests.yml

@@ -11,12 +11,13 @@ on:
 
 jobs:
   build:
-    runs-on: ubuntu-latest
     strategy:
       fail-fast: false
       matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
         python-version: ["3.10", "3.11", "3.12"]
 
+    runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v3
       - name: Set up Python ${{ matrix.python-version }}
@@ -39,6 +40,7 @@ jobs:
           pip install pytest pytest-cov
           pytest --cov-report html --cov="." tests/
       - name: Upload coverage data to smokeshow
+        if: ${{matrix.os == 'ubuntu-latest' && matrix.python-version == "3.12"}} # upload coverage once
         run: |
           pip install smokeshow
           smokeshow upload ./htmlcov