Unable to drag annotations when automatic scroll is enabled

[p-himik]

To reproduce:

1. Go to https://naomiaro.github.io/waveform-playlist/annotations.html
2. Enable Automatic Scroll at the bottom
3. Scroll the waveform so it's not at the starting position
4. Try dragging any annotation

Observed behavior: the waveform scrolling position is reset back to 0.
Expected behavior: the scrolling should not be affected at all by starting annotation dragging. Ideally, dragging an annotation close to a boundary of the player would scroll the waveform in the correct direction, but this probably deserves a separate feature request.

The root cause is that ScrollHook changes the position even when the playlist.isPlaying() is false, without any additional checks.