Don't close the hamburger menu when docks are toggled

[PiispaH]

In the db editor when toggling the visibility of the docks, the fact that you have to open the hamburger menu -> docks widget again every time after you make a change is frustrating. It would be much nicer if the menu would stay open and you could at the same time see what the docks that are currently selected would look like in their default positions.