Fix RSpec/MultipleSubjects cop (#24738)

spec/controllers/following_accounts_controller_spec.rb

@@ -39,10 +39,10 @@ describe FollowingAccountsController do
     end
 
     context 'when format is json' do
-      subject(:response) { get :index, params: { account_username: alice.username, page: page, format: :json } }
-
       subject(:body) { response.parsed_body }
 
+      let(:response) { get :index, params: { account_username: alice.username, page: page, format: :json } }
+
       context 'with page' do
         let(:page) { 1 }