[connect] don't set timeout handler to null after firing

Change-Id: Ie474b0d66cf8c9dcf921913a1c1ee476f21117fe
Reviewed-on: http://review.couchbase.org/28288
Tested-by: Mark Nunberg <mnunberg@haskalah.org>
Reviewed-by: Sergey Avseyev <sergey.avseyev@gmail.com>