Slashes are being escaped in entryPoint

[eadgbear]

Based off of one of the examples, I'm building the Docker file like so:

docker / dockerfile := {
  val artifact:File = assembly.value
  
  val depsArtifact:File = assemblyPackageDependency.value

  val jarTarget = s"//app/${artifact.getName}"
  val depTarget = s"/app/${depsArtifact.getName}"
  val classpathString = depTarget //+ ":" + jarTarget
  new Dockerfile {
    from("adoptopenjdk:" + dockerJavaVersion + "-jre-hotspot")
    add(depsArtifact, depTarget)
    add(artifact, jarTarget)
    entryPoint("java", "-cp", s"$classpathString", "-jar", jarTarget)
  }
}

I'm getting the following Dockerfile:

FROM adoptopenjdk:8-jre-hotspot
ADD 0/spark-eh-adx-assembly-0.0.1-deps.jar /app/spark-eh-adx-assembly-0.0.1-deps.jar
ADD 1/spark-eh-adx-assembly-0.0.1.jar //app/spark-eh-adx-assembly-0.0.1.jar
ENTRYPOINT ["java", "-cp", "\/app\/spark-eh-adx-assembly-0.0.1-deps.jar", "-jar", "\/\/app\/spark-eh-adx-assembly-0.0.1.jar"]

I added an extra slash to jarTarget as some debugging but I'm still getting the escaped slashes in the output.