Fruitsalad tab background doesn't match page background

[willgearty]

The tab background is hardcoded to be white, but admins can change the background of the whole page (@bodyBackground), so we probably want the tab background to be that same color.

ESP-Website/esp/esp/themes/theme_data/fruitsalad/less/main.less

Lines 377 to 378 in dadcfbe

	border-top-color: white;
	border-left-color: white;

and

ESP-Website/esp/esp/themes/theme_data/fruitsalad/less/main.less

Lines 387 to 388 in dadcfbe

	border-top-color: white;
	border-left-color: white;