Try 3.10 as string

.github/workflows/tests.yml

@@ -30,7 +30,7 @@ jobs:
     - name: Set up Python 3.10
       uses: actions/setup-python@v2
       with:
-        python-version: 3.10
+        python-version: "3.10"
     # Install EMMAA/test dependencies
     - name: Install dependencies
       run: |