"Move Selection to Current Level" can duplicate actors when cancelling

When moving an Actor that is referenced in the source level, UEditorEngine::CopySelectedActorsToClipboard will try to select the Actor for delete which will pull the \"Delete Referenced Actor\" dialog. If the user selects cancel to abort the move, the following steps complete and this results in duplicated instances of the referenced actor (Source and Dest levels). The problem seems to be that CopySelectedActorsToClipboard doesn't care for the return value of edactDeleteSelected so it can't abort the move operation.

1. Create a Persistent Level, and a sublevel
2. With the Persistent Level as the current level, place an Actor (e.g. Cube)
3. Create a reference variable in the Level Blueprint
4. Switch to the sublevel as the current level
5. From Editor Viewport Press Ctrl+M to move the selected actor to the current level (the sublevel)
6. The "Delete Referenced Actors" dialog appears (Move Level is a Cut-Paste operation; Cut is a Copy-Delete operation)
7. Cancel the Delete dialog — the rest of the action continues regardless, the Paste still happens, and you end up with two actors, one in each level