Fix geo_repository_created_event specs

This factory requires a project and wiki because of the call to
`wiki_path { project.wiki.disk_path }`

`build_stubbed` creates stubbed versions of these associations so it
works

ee/spec/models/concerns/geo/eventable_spec.rb

@@ -23,7 +23,7 @@ RSpec.describe Geo::Eventable do
 
   describe '#consumer_klass_name' do
     it 'returns the even class name without the module part' do
-      event = build(:geo_repository_created_event)
+      event = build_stubbed(:geo_repository_created_event)
 
       expect(event.consumer_klass_name).to eq 'RepositoryCreatedEvent'
     end

ee/spec/models/geo/event_log_spec.rb

@@ -53,7 +53,7 @@ RSpec.describe Geo::EventLog, type: :model do
     end
 
     it 'returns repository_created_event when set' do
-      repository_created_event = build(:geo_repository_created_event)
+      repository_created_event = build_stubbed(:geo_repository_created_event)
       subject.repository_created_event = repository_created_event
 
       expect(subject.event).to eq repository_created_event