Mark, I have seen that test class fail often both on personal machines and AWS instances.
I can't quantify as I haven't kept track of when it has happened, but I know it's that class. Here is a link to some discussion that happened around that class on slack https://the-asf.slack.com/archives/CERNB8NDC/p1560797596014800?thread_ts=1560797596.014800&cid=CERNB8NDC
