Use `let_it_be` to speed up specs

ee/spec/services/security/store_reports_service_spec.rb

@@ -3,10 +3,10 @@
 require 'spec_helper'
 
 RSpec.describe Security::StoreReportsService do
-  let(:user) { create(:user) }
-  let(:group) { create(:group) }
-  let(:project) { create(:project, :public, namespace: group) }
-  let(:pipeline) { create(:ci_pipeline, project: project) }
+  let_it_be(:user) { create(:user) }
+  let_it_be(:group) { create(:group) }
+  let_it_be(:project) { create(:project, :public, namespace: group) }
+  let_it_be(:pipeline) { create(:ci_pipeline, project: project) }
 
   describe '#execute' do
     subject(:execute_service_object) { described_class.new(pipeline).execute }
@@ -38,7 +38,7 @@ RSpec.describe Security::StoreReportsService do
       end
 
       it 'updates the `latest_pipeline_id` attribute of the associated `vulnerability_statistic` record' do
-        expect { execute_service_object }.to change { project.vulnerability_statistic&.latest_pipeline_id }.from(nil).to(pipeline.id)
+        expect { execute_service_object }.to change { project.reload.vulnerability_statistic&.latest_pipeline_id }.from(nil).to(pipeline.id)
       end
 
       context 'when StoreReportService returns an error for a report' do