Fix Resource Handling of `scalaStyleOnCompileConfig` in SparkBuild.scala

val scalaStyleOnCompileConfig: String = {
    val in = "scalastyle-config.xml"
    val out = "scalastyle-on-compile.generated.xml"
    val replacements = Map(
      """customId="println" level="error"""" -> """customId="println" level="warn""""
    )
    var contents = Source.fromFile(in).getLines.mkString("\n")
    for ((k, v) <- replacements) {
      require(contents.contains(k), s"Could not rewrite '$k' in original scalastyle config.")
      contents = contents.replace(k, v)
    }
    new PrintWriter(out) {
      write(contents)
      close()
    }
    out
  }