[Markdown] Allow XML elements in HtmlStash (#16486)

Author: emerardd

stubs/Markdown/markdown/util.pyi

@@ -2,6 +2,7 @@ from collections.abc import Iterator
 from importlib import metadata
 from re import Pattern
 from typing import Final, Generic, TypedDict, TypeVar, overload, type_check_only
+from xml.etree.ElementTree import Element
 
 from markdown.core import Markdown
 
@@ -45,11 +46,11 @@ class _TagData(TypedDict):
 
 class HtmlStash:
     html_counter: int
-    rawHtmlBlocks: list[str]
+    rawHtmlBlocks: list[str | Element]
     tag_counter: int
     tag_data: list[_TagData]
     def __init__(self) -> None: ...
-    def store(self, html: str) -> str: ...
+    def store(self, html: str | Element) -> str: ...
     def reset(self) -> None: ...
     def get_placeholder(self, key: int) -> str: ...
     def store_tag(self, tag: str, attrs: dict[str, str], left_index: int, right_index: int) -> str: ...