docs: reference latest version in README

Author: felix-seifert

README.md

@@ -21,7 +21,7 @@ steps:
 - uses: actions/checkout@v4
 - uses: actions/setup-python@v5
   with:
-    python-version: '3.12' 
+    python-version: '3.13' 
 - run: python my_script.py
 ```