sample-http-loadtest fails most of the time with ConcurrentModificationException

[turing85]

Citrus Version
2.8.0

Expected behavior
Test should pass.

Actual behavior
~10% of the time, the test will actually pass. In the other cases, the test will fail with:

[ERROR] testAddTodo(com.consol.citrus.samples.todolist.TodoListLoadTestIT)  Time elapsed: 0.535 s  <<< FAILURE!
com.consol.citrus.exceptions.TestCaseFailedException: Test case failed
Caused by: java.util.ConcurrentModificationException

Test case sample

> cd /path/to/citrus-samples
> mvn verify -Dembedded -pl :citrus-java-sample-http-loadtest
> mvn verify -Dembedded -pl :citrus-xml-sample-http-loadtest