Simplify resource_label_events API shared example

We don't need a repository, and we only need a private user in one
example, so we can scope it locally there.

spec/requests/api/resource_label_events_spec.rb

@@ -4,8 +4,7 @@ require 'spec_helper'
 
 describe API::ResourceLabelEvents do
   set(:user) { create(:user) }
-  set(:project) { create(:project, :public, :repository, namespace: user.namespace) }
-  set(:private_user) { create(:user) }
+  set(:project) { create(:project, :public, namespace: user.namespace) }
 
   before do
     project.add_developer(user)

spec/support/shared_examples/resource_label_events_api.rb

@@ -19,6 +19,7 @@ shared_examples 'resource_label_events API' do |parent_type, eventable_type, id_
 
     it "returns 404 when not authorized" do
       parent.update!(visibility_level: Gitlab::VisibilityLevel::PRIVATE)
+      private_user = create(:user)
 
       get api("/#{parent_type}/#{parent.id}/#{eventable_type}/#{eventable[id_name]}/resource_label_events", private_user)