fix iscoroutine

Author: KotlinIsland

stdlib/asyncio/coroutines.pyi

@@ -20,8 +20,4 @@ if sys.version_info < (3, 11):
 
 def iscoroutinefunction(func: object) -> bool: ...
 
-if sys.version_info >= (3, 8):
-    def iscoroutine(obj: object) -> TypeGuard[Coroutine[Any, Any, Any]]: ...
-
-else:
-    def iscoroutine(obj: object) -> TypeGuard[types.GeneratorType[Any, Any, Any] | Coroutine[Any, Any, Any]]: ...
+def iscoroutine(obj: object) -> TypeGuard[types.GeneratorType | Coroutine[Any, Any, Any]]: ...