[pywin32] win32gui.FindWindowEx parameters __ClassName and __WindowName are optional (#9859)

Author: bparzella

stubs/pywin32/win32/win32gui.pyi

@@ -135,7 +135,7 @@ def DestroyWindow(_hwnd: int) -> None: ...
 def EnableWindow(hWnd: int, bEnable): ...
 def FindWindow(__ClassName: _win32typing.PyResourceId | str | None, __WindowName: str | None) -> int: ...
 def FindWindowEx(
-    __Parent: int | None, __ChildAfter: int | None, __ClassName: _win32typing.PyResourceId | str, __WindowName: str
+    __Parent: int | None, __ChildAfter: int | None, __ClassName: _win32typing.PyResourceId | str | None, __WindowName: str | None
 ) -> int: ...
 def DragAcceptFiles(hwnd: int, fAccept) -> None: ...
 def DragDetect(hwnd: int, point: tuple[Incomplete, Incomplete]) -> None: ...