Fix passign full user object instead of id to Event.create

app/observers/activity_observer.rb

@@ -33,7 +33,7 @@ class ActivityObserver < BaseObserver
       target_id: record.id,
       target_type: record.class.name,
       action: status,
-      author_id: current_user
+      author_id: current_user.id
     )
   end
 end

app/observers/merge_request_observer.rb

@@ -46,7 +46,7 @@ class MergeRequestObserver < ActivityObserver
       target_id: record.id,
       target_type: record.class.name,
       action: status,
-      author_id: current_user
+      author_id: current_user.id
     )
   end
 end

spec/observers/activity_observer_spec.rb

@@ -8,7 +8,6 @@ describe ActivityObserver do
     it { @event.project.should == project }
   end
 
-
   describe "Issue created" do
     before do
       Issue.observers.enable :activity_observer do