Remove my mailmap entry.

.mailmap

@@ -51,7 +51,6 @@ Chris Pressey <cpressey@gmail.com>
 Chris Thorn <chris@thorn.co> Chris Thorn <thorn@thoughtbot.com>
 Clark Gaebel <cg.wowus.cg@gmail.com> <cgaebel@mozilla.com>
 Clinton Ryan <clint.ryan3@gmail.com>
-Corey Farwell <coreyf+rust@rwell.org> Corey Farwell <coreyf@rwell.org>
 Corey Richardson <corey@octayn.net> Elaine "See More" Nemo <corey@octayn.net>
 Cyryl Płotnicki <cyplo@cyplo.net>
 Damien Schoof <damien.schoof@gmail.com>