TMA-1700: Update unit test provisioning brick

Author: Dang Dinh

spec/unit/actions/provision_clients_spec.rb

@@ -39,7 +39,6 @@
     end
 
     it 'clean all zombie clients' do
-      expect(GoodData::LCM2::PurgeClients).to receive(:call).and_return(results: [], params: { client_projects: [] })
       expect { subject.class.call(params) }.to raise_error('limit reached')
     end
   end