Ensure brand prefixed favicon is used

services/web/app/views/general/500.pug

@@ -2,7 +2,7 @@ doctype html
 html.full-height(itemscope, itemtype='http://schema.org/Product')
 	head
 		title Something went wrong
-		link(rel="icon", href="/favicon.ico")
+		link(rel="icon", href="/" + settings.brandPrefix + "favicon.ico")
 		if buildCssPath
 			link(rel="stylesheet", href=buildCssPath("/" + settings.brandPrefix + "style.css"))
 		link(href="//netdna.bootstrapcdn.com/font-awesome/4.2.0/css/font-awesome.min.css",rel="stylesheet")