Removes batch_review_notification feature flag

This feature flag was being used as a gatekeeper
for the one notification for every batch review
feature.

We no longer require the feature flag since the
code is working as expected

ee/app/services/draft_notes/publish_service.rb

@@ -27,21 +27,15 @@ module DraftNotes
     def publish_draft_notes
       return if draft_notes.empty?
 
-      if Feature.enabled?(:batch_review_notification, project)
       review = Review.create!(author: current_user, merge_request: merge_request, project: project)
 
       draft_notes.map do |draft_note|
         draft_note.review = review
         create_note_from_draft(draft_note)
       end
-
-        notification_service.async.new_review(review)
-      else
-        draft_notes.each(&method(:create_note_from_draft))
-      end
-
       draft_notes.delete_all
 
+      notification_service.async.new_review(review)
       MergeRequests::ResolvedDiscussionNotificationService.new(project, current_user).execute(merge_request)
     end
 

ee/spec/services/draft_notes/publish_service_spec.rb

@@ -65,7 +65,6 @@ describe DraftNotes::PublishService do
       expect(DraftNote.count).to eq(0)
     end
 
-    context 'when batch_review_notification feature is enabled' do
     it 'sends batch notification' do
       expect_next_instance_of(NotificationService) do |notification_service|
         expect(notification_service).to receive_message_chain(:async, :new_review).with(kind_of(Review))
@@ -75,21 +74,6 @@ describe DraftNotes::PublishService do
     end
   end
 
-    context 'when batch_review_notification feature is disabled' do
-      it 'send a notification for each note' do
-        stub_feature_flags(batch_review_notification: false)
-
-        2.times do
-          expect_next_instance_of(NotificationService) do |notification_service|
-            expect(notification_service).to receive(:new_note).with(kind_of(Note))
-          end
-        end
-
-        publish
-      end
-    end
-  end
-
   it 'only publishes the draft notes belonging to the current user' do
     other_user = create(:user)
     project.add_maintainer(other_user)