Disable tag updating from inline editor.
This mitigates a potential data-loss situation that might happen when
adding new music items:
Juk starts processing the new items in addFiles, Results in a new CollectionListItem being created, The resultant PlaylistItem superclass calls setFlags, This causes Qt to send a *data* changed signal from the QTreeWidget holding all the playlist items, saying that a *different* QTreeWidgetItem / PlaylistItem has been changed. This signal is normally only possible because of user interaction with the inline editor. As a result JuK assumes the signal is a user request to edit the track's tag, and does so. I have seen this cause existing files to take on the same tag values as one of the incoming new tracks.
Although in theory a user could immediately select the "Undo" command to
fix this, that's not a very good workaround. Since we have a separate
tag editor already, we'll just use that instead until we can figure out
a way to ensure that dataChanged signals are sent only when the data
itself has changed (not just flags caused by unrelated items being
CHANGELOG: Prevent opening new items from inadvertently editing track metadata on existing items.