Use typeshed.Incomplete and object instead of Any in tkinter stubs (#8458)

Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>

stdlib/tkinter/dialog.pyi

@@ -1,4 +1,5 @@
 import sys
+from _typeshed import Incomplete
 from collections.abc import Mapping
 from tkinter import Widget
 from typing import Any
@@ -11,5 +12,5 @@ DIALOG_ICON: str
 class Dialog(Widget):
     widgetName: str
     num: int
-    def __init__(self, master: Any | None = ..., cnf: Mapping[str, Any] = ..., **kw) -> None: ...
+    def __init__(self, master: Incomplete | None = ..., cnf: Mapping[str, Any] = ..., **kw) -> None: ...
     def destroy(self) -> None: ...