Remove checkTraceLevel from scripted test

sbt-app/src/sbt-test/actions/streams-trace-level/build.sbt

@@ -1,6 +1,5 @@
 lazy val helloWithoutStreams = taskKey[Unit]("")
 lazy val helloWithStreams = taskKey[Unit]("")
-lazy val checkTraceLevel = taskKey[Unit]("")
 
 helloWithoutStreams := {
   throw new RuntimeException("boom without streams!")
@@ -10,8 +9,3 @@ helloWithStreams := {
   val log = streams.value.log
   throw new RuntimeException("boom with streams!")
 }
-
-checkTraceLevel := {
-  val level = traceLevel.value
-  assert(level != -1, s"Expected traceLevel != -1 in batch mode, but got $level")
-}

sbt-app/src/sbt-test/actions/streams-trace-level/test

@@ -1,3 +1,2 @@
 -> helloWithoutStreams
 -> helloWithStreams
-> checkTraceLevel