Fix alert EE specs

ee/spec/factories/prometheus_alert.rb

 FactoryBot.define do
   factory :prometheus_alert do
     project
-    environment
-    prometheus_metric
     operator :gt
     threshold 1
+
+    environment do |alert|
+      build(:environment, project: alert.project)
+    end
+
+    prometheus_metric do |alert|
+      build(:prometheus_metric, project: alert.project)
+    end
   end
 end

ee/spec/services/projects/prometheus/metrics/destroy_service_spec.rb

@@ -13,7 +13,7 @@ describe Projects::Prometheus::Metrics::DestroyService do
 
   context 'when metric has a prometheus alert associated' do
     it 'schedules a prometheus alert update' do
-      create(:prometheus_alert, prometheus_metric: metric)
+      create(:prometheus_alert, project: metric.project, prometheus_metric: metric)
 
       schedule_update_service = spy
       allow(::Clusters::Applications::ScheduleUpdateService).to receive(:new).and_return(schedule_update_service)

ee/spec/services/projects/prometheus/metrics/update_service_spec.rb

@@ -13,7 +13,7 @@ describe Projects::Prometheus::Metrics::UpdateService do
     let(:schedule_update_service) { spy }
 
     before do
-      create(:prometheus_alert, prometheus_metric: metric)
+      create(:prometheus_alert, project: metric.project, prometheus_metric: metric)
       allow(::Clusters::Applications::ScheduleUpdateService).to receive(:new).and_return(schedule_update_service)
     end