Fix formatting of python-version in CI matrix making 3.10 issues

Author: Martin Møldrup

.github/workflows/continuous_integration.yaml

@@ -39,10 +39,10 @@ jobs:
         strategy:
           fail-fast: false
           matrix:
-            python-version: [3.10, 3.13]
+            python-version: ["3.10", "3.13"]
             include-extras: [true]
             include:
-              - python-version: 3.9
+              - python-version: "3.9"
                 include-extras: false
 
         steps: