[2.x] sbtn run errors out #8256
Description
steps
$ sbt run
problem
$ sbt run
[info] running (fork) example.Hello
Error: Could not find or load main class @.var.folders.hg.2602nfrs2958vnshglyl3srw0000gn.T.sbt-args7315803247162000786.tmp
Exception in thread "sbt-serverconnection-0" nonzero exit code returned from runner: 1
at sbt.Run$.processExitCode(Run.scala:195)
at sbt.ForkRun.run(Run.scala:38)
at sbt.internal.client.NetworkClient.jvmRun$1(NetworkClient.scala:756)
at sbt.internal.client.NetworkClient.clientSideRun(NetworkClient.scala:780)