Remove superfluous call to #create_new_auth_token.

 * There was prior discussion around removing this line of code, inside
   lynndylanhurley#990.
   See: lynndylanhurley#990 (comment)

 * While line in question _is_ superfluous, removing it was blocked by a
   bad test.  This test was corrected in the previous commit (9ebc5bd).

app/controllers/devise_token_auth/concerns/set_user_by_token.rb

@@ -60,7 +60,9 @@ def set_user_by_token(mapping=nil)
       if devise_warden_user && devise_warden_user.tokens[@client_id].nil?
         @used_auth_by_token = false
         @resource = devise_warden_user
-        @resource.create_new_auth_token
+        # REVIEW: The following line _should_ be safe to remove;
+        #  the generated token does not get used anywhere.
+        # @resource.create_new_auth_token
       end
     end