Fix mypy to 1.13.0 to avoid __all__ duplication

Author: MyreMylar

.github/workflows/build-ubuntu-sdist.yml

@@ -84,7 +84,7 @@ jobs:
 
     - name: Test typestubs
       run: |
-        pip3 install mypy
+        pip3 install mypy==1.13.0
         python3 buildconfig/stubs/stubcheck.py
 
     # We upload the generated files under github actions assets