Record python envs as strings so that 3.10 doesn't get rounded to 3.1

Author: jinnatar

.github/workflows/tox_testing.yml

@@ -12,7 +12,7 @@ jobs:
     strategy:
       max-parallel: 5
       matrix:
-        python-version: [3.8, 3.9, 3.10]
+        python-version: ["3.8", "3.9", "3.10"]
 
     steps:
     - uses: actions/checkout@v1