Fix arguments comment

Author: link2xt

src/receive_imf.rs

@@ -2139,7 +2139,7 @@ async fn create_group(
 /// original system message.
 ///
 /// * `to_ids` - contents of the `To` and `Cc` headers.
-/// * `is_partial_download` - whether the message is not fully downloaded.
+/// * `past_ids` - contents of the `Chat-Group-Past-Members` header.
 #[allow(clippy::too_many_arguments)]
 async fn apply_group_changes(
     context: &Context,