use update service on ldap call and updated specs and service

app/services/users/update_service.rb

@@ -7,14 +7,30 @@ module Users
       @params = params.dup
     end
 
-    def execute(skip_authorization: false)
-      raise Gitlab::Access::AccessDeniedError unless skip_authorization || can_update_user?
+    def execute(skip_authorization: false, &block)
+      assign_attributes(skip_authorization, &block)
 
-      if @user.update_attributes(params)
+      if @user.save
         success
       else
-        error('Project could not be updated')
+        error('User could not be updated')
+      end
+    end
+
+    def execute!(skip_authorization: false, &block)
+      assign_attributes(skip_authorization, &block)
+
+      @user.save!
     end
+
+    private
+
+    def assign_attributes(skip_authorization, &block)
+      raise Gitlab::Access::AccessDeniedError unless skip_authorization || can_update_user?
+
+      yield(@user) if block_given?
+
+      @user.assign_attributes(params) if params.any?
     end
 
     def can_update_user?

lib/gitlab/o_auth/user.rb

@@ -32,7 +32,7 @@ module Gitlab
 
         block_after_save = needs_blocking?
 
-        gl_user.save!
+        Users::UpdateService.new(gl_user, gl_user).execute!
 
         gl_user.block if block_after_save
 

spec/models/user_spec.rb

@@ -1900,7 +1900,6 @@ describe User, models: true do
     end
   end
 
-
   describe 'audit changes' do
     let!(:user) { create(:user) }