Use Python 3.7 for tox envs that don't start with py

job--python-tox.yml

@@ -33,6 +33,9 @@ jobs:
           ${{ if or(eq(env, 'py38'), startsWith(env, 'py38-')) }}:
             py: '3.7'
             ispy38: true
+          # Use Python 3.7 by default for toxenvs that don't start with 'py'
+          ${{ if not(startsWith(env, 'py')) }}:
+            py: '3.7'
 
   pool:
     ${{ if eq(parameters.os, 'linux') }}: