Add reviewed and unreviewed scopes to Reviewable model concern (#31988)

spec/models/preview_card_provider_spec.rb

@@ -24,21 +24,5 @@ RSpec.describe PreviewCardProvider do
         expect(results).to eq([not_trendable_and_not_reviewed])
       end
     end
-
-    describe 'reviewed' do
-      it 'returns the relevant records' do
-        results = described_class.reviewed
-
-        expect(results).to eq([trendable_and_reviewed])
-      end
-    end
-
-    describe 'pending_review' do
-      it 'returns the relevant records' do
-        results = described_class.pending_review
-
-        expect(results).to eq([not_trendable_and_not_reviewed])
-      end
-    end
   end
 end