Use PEP 570 syntax in comments (#11552)

stdlib/zipfile/__init__.pyi

@@ -44,7 +44,7 @@ class _ZipStream(Protocol):
     # The following methods are optional:
     # def seekable(self) -> bool: ...
     # def tell(self) -> int: ...
-    # def seek(self, __n: int) -> object: ...
+    # def seek(self, n: int, /) -> object: ...
 
 # Stream shape as required by _EndRecData() and _EndRecData64().
 class _SupportsReadSeekTell(Protocol):