Big diff: Use new "|" union syntax (#5872)

stdlib/ctypes/util.pyi

@@ -1,7 +1,6 @@
 import sys
-from typing import Optional
 
-def find_library(name: str) -> Optional[str]: ...
+def find_library(name: str) -> str | None: ...
 
 if sys.platform == "win32":
-    def find_msvcrt() -> Optional[str]: ...
+    def find_msvcrt() -> str | None: ...