Attach duration information to the exception object

spec/lib/runner/strategy/docker_container_pool_spec.rb

@@ -261,18 +261,10 @@ describe Runner::Strategy::DockerContainerPool do
   end
 
   describe '#attach_to_execution' do
-    # TODO: add more tests here
+    # TODO: add tests here
 
     let(:command) { 'ls' }
     let(:action) { -> { container_pool.attach_to_execution(command) } }
     let(:websocket_url) { 'ws://ws.example.com/path/to/websocket' }
-
-    it 'returns the execution time' do
-      allow(EventMachine).to receive(:run)
-      starting_time = Time.zone.now
-      execution_time = action.call
-      test_time = Time.zone.now - starting_time
-      expect(execution_time).to be_between(0.0, test_time).exclusive
-    end
   end
 end