Clean unused imports in .pyi files

src/Mod/Sketcher/App/ExternalGeometryExtension.pyi

@@ -4,7 +4,6 @@ from __future__ import annotations
 
 from Base.Metadata import export, constmethod
 from Part.App.GeometryExtension import GeometryExtension
-from typing import Final, overload
 
 @export(
     PythonName="Sketcher.ExternalGeometryExtension",

src/Mod/Sketcher/App/Sketch.pyi

@@ -2,7 +2,7 @@
 
 from __future__ import annotations
 
-from Base.Metadata import export, constmethod
+from Base.Metadata import export
 from Base.Persistence import Persistence
 from Base.Vector import Vector
 from typing import Final, Tuple