High contrast: minimap selection color does not match editor selection color

[isidorn]

Refs: #81689

Every theme the selection color matches in the editor and in the minimap. However in the High Contrast theme that is not the case.
I do not understand the incosistency here and I would suggest that we use the same white color as in the editor.
I like how the current solution wokrs so I can be conviced that we should go with that one, I just do not like the inconsistency.

fyi @misolori

[isidorn]

Another downside of this approach is that the search decoration are not that visible (orange on yellow)

[RMacfarlane]

Nice catch, I didn't notice this before. High contrast mode seems to use some other color than editor.selectionBackground as the editor color here. I'll update to match that color 👍

[isidorn]

Adding bug and milestone so we verify this. Thanks for fixing.