Detach completion confirmation task when selecting with mouse

Otherwise the spawn to resolve the additional edits never runs causing
autocomplete to never add imports automatically when clicking with the
mouse

crates/editor/src/editor.rs

@@ -1057,7 +1057,8 @@ impl CompletionsMenu {
                                     item_ix: Some(item_ix),
                                 },
                                 cx,
-                            );
+                            )
+                            .map(|task| task.detach());
                         })
                         .into_any(),
                     );