Sleep longer to overcome shutdown hook concurrency
Sleep longer to overcome shutdown hook concurrency

Fixes scala/bug#11536

https://docs.oracle.com/javase/8/docs/api/java/lang/Runtime.html#addShutdownHook-java.lang.Thread-

> When the virtual machine begins its shutdown sequence it will start all registered shutdown hooks in some unspecified order and let them run concurrently

scala/scala,lrytz/scala,scala/scala,martijnhoekstra/scala,lrytz/scala,scala/scala,martijnhoekstra/scala,scala/scala,lrytz/scala,martijnhoekstra/scala,martijnhoekstra/scala,lrytz/scala,martijnhoekstra/scala,lrytz/scala,scala/scala,scala/scala,martijnhoekstra/scala,lrytz/scala