[pydoc] Use StrPath for ispackage function (#15252)

Source: https://github.com/python/cpython/blob/aa8578dc54df2af9daa3353566359e602e5905cf/Lib/pydoc.py#L293

Author: donbarbos

stdlib/pydoc.pyi

@@ -1,5 +1,5 @@
 import sys
-from _typeshed import OptExcInfo, SupportsWrite, Unused
+from _typeshed import OptExcInfo, StrPath, SupportsWrite, Unused
 from abc import abstractmethod
 from builtins import list as _list  # "list" conflicts with method name
 from collections.abc import Callable, Container, Mapping, MutableMapping
@@ -35,10 +35,10 @@ def classify_class_attrs(object: object) -> list[tuple[str, str, type, str]]: ..
 
 if sys.version_info >= (3, 13):
     @deprecated("Deprecated since Python 3.13.")
-    def ispackage(path: str) -> bool: ...  # undocumented
+    def ispackage(path: StrPath) -> bool: ...  # undocumented
 
 else:
-    def ispackage(path: str) -> bool: ...  # undocumented
+    def ispackage(path: StrPath) -> bool: ...  # undocumented
 
 def source_synopsis(file: IO[AnyStr]) -> AnyStr | None: ...
 def synopsis(filename: str, cache: MutableMapping[str, tuple[int, str]] = {}) -> str | None: ...