ci: test on both python 3.7 and 3.10

.github/workflows/ci.yml

@@ -11,11 +11,15 @@ jobs:
 
     runs-on: ubuntu-latest
 
+    strategy:
+      matrix:
+        python: ['3.7', '3.10']
+
     steps:
     - uses: actions/checkout@v3
     - uses: actions/setup-python@v4
       with:
-        python-version: '3.7'
+        python-version: ${{matrix.python}}
         cache: 'pip'
     - name: Install dependencies
       run: pip install -r requirements.txt