Improve many __(a)exit__ annotations (#9696)

stubs/psutil/psutil/__init__.pyi

@@ -218,7 +218,7 @@ class Process:
 class Popen(Process):
     def __init__(self, *args, **kwargs) -> None: ...
     def __enter__(self) -> Self: ...
-    def __exit__(self, *args, **kwargs) -> None: ...
+    def __exit__(self, *args: object, **kwargs: object) -> None: ...
     def __getattribute__(self, name: str) -> Any: ...
 
 def pids() -> list[int]: ...