The editor clock, which is responsible for performing the seek, was not
aware of changes in control points due to reading from the wrong
beatmap. `loadableBeatmap` is not actually changed by any of the editor
components; `playableBeatmap` and `editorBeatmap` are.
For now this is changed to use `playableBeatmap`. A better follow-up
would be to use `editorBeatmap`, but it would probably be best to move
the beat snap bindable into `EditorBeatmap` first.
