SBT 1.3.3 breaks sbt-docker-compose

[leo-bogastry]

I have been successfully using sbt-docker-compose to facilitate some testing. Previous sbt version was 1.2.8, but we are now updating to sbt 1.3.3 with which the dockerComposeTest command fails with error:

my.test.testSpec *** ABORTED ***
java.lang.RuntimeException: Unable to load a Suite class that was discovered in the runpath: my.test.testSpec
at org.scalatest.tools.DiscoverySuite$.getSuiteInstance(DiscoverySuite.scala:81)
at org.scalatest.tools.DiscoverySuite$$anonfun$1.apply(DiscoverySuite.scala:38)
at org.scalatest.tools.DiscoverySuite$$anonfun$1.apply(DiscoverySuite.scala:37)
at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:234)
at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:234)
at scala.collection.Iterator$class.foreach(Iterator.scala:893)
at scala.collection.AbstractIterator.foreach(Iterator.scala:1336)
at scala.collection.IterableLike$class.foreach(IterableLike.scala:72)
at scala.collection.AbstractIterable.foreach(Iterable.scala:54)
at scala.collection.TraversableLike$class.map(TraversableLike.scala:234)