Objective display in top center of HUD should be scalable in HUD options

The current HUD options allow scaling of the objective markers on screen which hover on top of the objective areas, but the main objective display which is always visible on top of the screen cannot be scaled down.

On my 1440p display, the main objective HUD takes way too much screen space in my opinion, and it would feel appropriate to have a separate control for the objective display scale, in similar fashion as the objective markers are currently customisable.