Update testing_multiversion.yml

Limit test versions to allowd versions

Author: rettigl

.github/workflows/testing_multiversion.yml

@@ -12,7 +12,7 @@ jobs:
     # Using matrix strategy
     strategy:
       matrix:
-        python-version: ["3.8", "3.9", "3.10", "3.11"]
+        python-version: ["3.8", "3.9", "3.10", "3.11.8"]
     runs-on: ubuntu-latest
     steps:
       # Check out repo and set up Python