revert back spec change and use a different cleanup strategy for spec that was...

revert back spec change and use a different cleanup strategy for spec that was forcing a transaction commit

spec/services/destroy_group_service_spec.rb

@@ -55,6 +55,10 @@ describe DestroyGroupService, services: true do
 
     context 'potential race conditions' do
       context "when the `GroupDestroyWorker` task runs immediately" do
+        before do
+          DatabaseCleaner.strategy = :deletion
+        end
+
         it "deletes the group" do
           # Commit the contents of this spec's transaction so far
           # so subsequent db connections can see it.

spec/workers/admin_emails_worker_spec.rb

 require 'spec_helper'
 
 describe AdminEmailsWorker do
-  include EmailHelpers
-
   context "recipients" do
     let(:group) { create :group }
     let(:project) { create :project }
@@ -20,7 +18,7 @@ describe AdminEmailsWorker do
       blocked_user = create(:user, state: :blocked)
       group.add_user(blocked_user, Gitlab::Access::DEVELOPER)
       project.add_user(blocked_user, Gitlab::Access::DEVELOPER)
-      reset_delivered_emails!
+      ActionMailer::Base.deliveries = []
     end
 
     context "sending emails to members of a group only" do