Try Py 3.10 on the Trav runner?

.github/workflows/build_and_test.yml

@@ -33,7 +33,7 @@ jobs:
       - uses: actions/checkout@v2
       - uses: actions/setup-python@v2
         with:
-          python-version: '3.12'
+          python-version: '3.10'
       - name: Install Dependencies
         run: pip3 install -r requirements.txt
 #      - name: Setup tmate session