Fix Event#reset_project_activity updates

!6678 removed the lease from Event#reset_project_activity, but it wasn't
actually updating the project's last_activity_at timestamp properly.
The WHERE clause would always return no matching projects. The spec
passed occasionally because the created_at timestamp was automatically
set to last_activity_at.

app/models/event.rb

@@ -335,7 +335,7 @@ class Event < ActiveRecord::Base
     # update the project. Only one query should actually perform the update,
     # hence we add the extra WHERE clause for last_activity_at.
     Project.unscoped.where(id: project_id).
-      where('last_activity_at > ?', RESET_PROJECT_ACTIVITY_INTERVAL.ago).
+      where('last_activity_at <= ?', RESET_PROJECT_ACTIVITY_INTERVAL.ago).
       update_all(last_activity_at: created_at)
   end

spec/models/project_spec.rb

@@ -308,7 +308,9 @@ describe Project, models: true do
   end
   describe 'last_activity methods' do
-    let(:project) { create(:project, last_activity_at: 2.hours.ago) }
+    let(:timestamp) { 2.hours.ago }
+    # last_activity_at gets set to created_at upon creation
+    let(:project) { create(:project, created_at: timestamp, updated_at: timestamp) }
     describe 'last_activity' do
       it 'alias last_activity to last_event' do
@@ -322,6 +324,7 @@ describe Project, models: true do
       it 'returns the creation date of the project\'s last event if present' do
         new_event = create(:event, project: project, created_at: Time.now)
+        project.reload
         expect(project.last_activity_at.to_i).to eq(new_event.created_at.to_i)
       end