Test for only one Python version locally

Test for only one Python version locally, or it will be too time consuming.
(Build tests for four Python versions will be added to CI).

Author: HannoSpreeuw

pyproject.toml

@@ -54,7 +54,7 @@ packages = ["sourcefinder"]
 
 [tool.hatch.envs.test]
 matrix = [
-    {python = ["3.10", "3.11", "3.12", "3.13"]}
+    {python = ["3.12"]}
 ]
 extra-dependencies = [
     "pytest",