fix: use bash shell for Windows test step

PowerShell doesn't expand dist/*.whl glob, so pip never installs
the wheel. Force bash shell for cross-platform glob support.

Author: semihalev

.github/workflows/ci.yml

@@ -97,6 +97,7 @@ jobs:
           path: dist
 
       - name: Install wheel and test dependencies
+        shell: bash
         run: |
           pip install dist/*.whl
           pip install pytest pytest-asyncio