CURA-12093
In this context, the tooltip is quite useless, and causes some issues because it sometimes appears when you don't want to. Moreover, the next commit will add a link to a detailed documentation.
Also fix the highlight colour of the border. The highlight colour was changed in a later design but it was not changed here yet.
Without a theme colour it's going to use the system colours for the highlighting of text, which may be a very light grey that matches the background, making it impossible to see what part of the text is selected.
Hopefully fixes issue #12286.
This then updates in a fraction of a millisecond later before things even appear on the screen, so it's not so bad to not have a tooltip or to have it show 0 then.
Done during Turbo Testing and Tooling.
