Update python-package.yml

鎖定在3.10

.github/workflows/python-package.yml

@@ -12,7 +12,7 @@ jobs:
     - name: Set up Python
       uses: actions/setup-python@v2
       with:
-        python-version: '3.x'
+        python-version: '3.10'
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip