Broken Builds in Jenkins

[Stephen Mallette <sp...@gmail.com>]

As we are now using PRs for most commits, we'd save some time for ourselves
by letting Jenkins OK the PR by building/testing it so that all the
reviewers need to typically do is look at the code itself. I say
"typically" as there will be cases where integration tests may need to be
executed or some other checks done, but Jenkins can go a long way to saving
us time on most PRs.

To get there, we need to figure out why the regular Jenkins build of master
is busted.  Right now these same five tests seem to fail over and over
again:

https://builds.apache.org/view/All/job/tinkerpop-master/1093/org.apache.tinkerpop$spark-gremlin/testReport/

You can click on any of those tests to see the output, but here's a gist
just in case of a problem:

https://gist.github.com/spmallette/8256f92b2ee30cf6561c

Any clues on what's amiss here?  how do we fix this?