I've seen a couple intermittent failures in CI runs:

https://ci.wildfly.org/project.html?projectId=WildFlyCore&buildTypeId=&tab=testDetails&testNameId=-4143278160763350583&order=TEST_STATUS_DESC&branch_WildFlyCore=__all_branches__&itemsCount=50

I think the cause is the test is doing a reload of the HC but is not waiting for the connection to close.