community-build: actually turn off supershell

The option was passed in the wrong place so wasn't actually set most of
the time.

Author: smarter

community-build/test/scala/dotty/communitybuild/CommunityBuildTest.scala

@@ -103,10 +103,11 @@ final case class SbtCommunityProject(
   override val runCommandsArgs: List[String] =
     // Run the sbt command with the compiler version and sbt plugin set in the build
     val sbtProps = Option(System.getProperty("sbt.ivy.home")) match
-      case Some(ivyHome) => List(s"-Dsbt.ivy.home=$ivyHome", "-Dsbt.supershell=false")
+      case Some(ivyHome) => List(s"-Dsbt.ivy.home=$ivyHome")
       case _ => Nil
     extraSbtArgs ++ sbtProps ++ List(
       "-sbt-version", "1.3.8",
+       "-Dsbt.supershell=false",
       s"--addPluginSbtFile=$sbtPluginFilePath")
 
 object projects: