Update actions/setup-python action to v5

Author: renovate[bot]

.github/workflows/readthedocs.yml

@@ -14,7 +14,7 @@ jobs:
             uses: actions/checkout@v2
 
           - name: Set up Python
-            uses: actions/setup-python@v2
+            uses: actions/setup-python@v5
             with:
                 python-version: 3.x