Webrick gem test failure: Leaked thread

[gogainda]

Full log: https://gist.github.com/gogainda/4606b4ef66d35a9436ff7be8577620d7

Haven't seen it before for Webrick

Leaked thread: TestWEBrickHTTPAuth#test_digest_auth_invalid: #<Thread:0x7e98@/Users/novoi/.rubies/truffleruby-dev/lib/truffle/timeout.rb:127 sleep>
[ 33/134] TestWEBrickHTTPProxy#test_connect[To redirect Truffle log output to a file use one of the following options:
* '--log.file=<path>' if the option is passed using a guest language launcher.
* '-Dpolyglot.log.file=<path>' if the option is passed using the host Java launcher.
* Configure logging using the polyglot embedding API.]
[ruby] SEVERE: waited 5 seconds in the SafepointManager but 2 of 12 threads did not arrive - a thread is likely making a blocking call - reason for the safepoint: Thread#kill
Dumping stacktraces of all threads:
BLOCKED: Thread[Ruby Thread id=325 from /Users/novoi/tmp/webrick/test/webrick/utils.rb:65,5,main]
com.oracle.svm.core.posix.headers.Pthread.pthread_cond_wait(Pthread.java)
com.oracle.svm.core.posix.thread.PosixParkEvent.condWait(PosixJavaThreads.java:250)
com.oracle.svm.core.thread.JavaThreads.park(JavaThreads.java:688)
sun.misc.Unsafe.park(Unsafe.java:49)
java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
...