Switch to PEP-604 syntax in python2 stubs (#5915)

Signed-off-by: oleg.hoefling <oleg.hoefling@gmail.com>

stdlib/@python2/urlparse.pyi

@@ -1,4 +1,4 @@
-from typing import AnyStr, Dict, List, NamedTuple, Optional, Sequence, Tuple, Union, overload
+from typing import AnyStr, Dict, List, NamedTuple, Sequence, Tuple, Union, overload
 
 _String = Union[str, unicode]
 
@@ -15,13 +15,13 @@ def clear_cache() -> None: ...
 
 class ResultMixin(object):
     @property
-    def username(self) -> Optional[str]: ...
+    def username(self) -> str | None: ...
     @property
-    def password(self) -> Optional[str]: ...
+    def password(self) -> str | None: ...
     @property
-    def hostname(self) -> Optional[str]: ...
+    def hostname(self) -> str | None: ...
     @property
-    def port(self) -> Optional[int]: ...
+    def port(self) -> int | None: ...
 
 class _SplitResult(NamedTuple):
     scheme: str