Add tox to run on windows

Author: soimkim

.github/workflows/pull-request.yml

@@ -17,7 +17,7 @@ jobs:
     strategy:
       matrix:
         python-version: [3.8, 3.11]
-        os: [ubuntu-latest, macos-latest]
+        os: [ubuntu-latest, macos-latest, windows-latest]
     runs-on: ${{ matrix.os }}
     steps:
     - uses: actions/checkout@v3