Put back deleted :unfiltered_epic_aggregates feature flag test

Put back test since we are just defaulting flags to on

ee/app/graphql/types/epic_type.rb

@@ -135,7 +135,9 @@ module Types
     field :descendant_weight_sum, Types::EpicDescendantWeightSumType, null: true, complexity: 10,
       description: "Total weight of open and closed issues in the epic and its descendants",
       resolve: -> (epic, args, ctx) do
-        Gitlab::Graphql::Aggregations::Epics::LazyEpicAggregate.new(ctx, epic.id, WEIGHT_SUM)
+        if Feature.enabled?(:unfiltered_epic_aggregates, epic.group, default_enabled: true)
+          Gitlab::Graphql::Aggregations::Epics::LazyEpicAggregate.new(ctx, epic.id, WEIGHT_SUM)
+        end
       end
 
     field :health_status, Types::EpicHealthStatusType, null: true, complexity: 10,

ee/spec/requests/api/graphql/group/epic/epic_aggregate_query_spec.rb

@@ -108,5 +108,53 @@ describe 'Epic aggregates (count and weight)' do
         )
       end
     end
+
+    context 'with feature flag disabled' do
+      before do
+        stub_feature_flags(unfiltered_epic_aggregates: false)
+      end
+
+      context 'when requesting counts' do
+        let(:epic_aggregates_query) do
+          <<~QUERY
+          nodes {
+            descendantCounts {
+              openedEpics
+              closedEpics
+              openedIssues
+              closedIssues
+            }
+          }
+          QUERY
+        end
+
+        it 'uses the DescendantCountService' do
+          expect(Epics::DescendantCountService).to receive(:new)
+
+          post_graphql(query, current_user: current_user)
+        end
+
+        it_behaves_like 'counts properly'
+      end
+
+      context 'when requesting weights' do
+        let(:epic_aggregates_query) do
+          <<~QUERY
+          nodes {
+            descendantWeightSum {
+              openedIssues
+              closedIssues
+            }
+          }
+          QUERY
+        end
+
+        it 'returns nil' do
+          post_graphql(query, current_user: current_user)
+
+          expect(subject).to include(a_hash_including('descendantWeightSum' => nil))
+        end
+      end
+    end
   end
 end