Bump lower Python version tested to 3.9

Author: emanlove

.github/workflows/CI.yml

@@ -9,7 +9,7 @@ jobs:
     continue-on-error: true
     strategy:
       matrix:
-        python-version: [3.8, 3.13.0]  # pypy-3.9
+        python-version: [3.9, 3.13.0]  # pypy-3.9
         rf-version: [6.1.1, 7.2.2, 7.3]
         selenium-version: [4.32.0, 4.33.0]
         browser: [firefox, chrome, headlesschrome]  #edge