Debug option to hide player HUD (including `LevelTime` counter) #2799

Job	Run time
clickable (Debug, amd64, glew)	11m 57s
clickable (Debug, amd64, sdl)	11m 12s
clickable (Debug, armhf, glew)	11m 21s
clickable (Debug, armhf, sdl)	10m 19s
clickable (Release, amd64, glew)	11m 9s
clickable (Release, amd64, sdl)	10m 59s
clickable (Release, arm64, glew)	11m 42s
clickable (Release, arm64, sdl)	11m 13s
clickable (Release, armhf, glew)	10m 19s
clickable (Release, armhf, sdl)	10m 3s
	1h 50m 14s

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