Fix argument type of html.escape and html.unescape (#15731)

Author: max-kamps

stdlib/html/__init__.pyi

@@ -1,6 +1,4 @@
-from typing import AnyStr
-
 __all__ = ["escape", "unescape"]
 
-def escape(s: AnyStr, quote: bool = True) -> AnyStr: ...
-def unescape(s: AnyStr) -> AnyStr: ...
+def escape(s: str, quote: bool = True) -> str: ...
+def unescape(s: str) -> str: ...