Remove $wgGoToEdit functionality

SpecialSearchNogomatch can be used with a 1 liner to accomplish the
same thing. In fact, there's an extension (BypassSearch) that already
does this.

Change-Id: I5d7e56ec6fe1110e29ac5c8ba5482b8fc2bf1956
(cherry picked from commit 43df36eceb6b1200b6d1eb6b42e8ef21c65a8832)