in ratatool-diffy/src/main/scala/com/spotify/ratatool/diffy/AvroDiffy.scala [52:56]
private def isRecord(schema: Schema): Boolean = schema.getType match {
case Schema.Type.RECORD => true
case Schema.Type.UNION => schema.getTypes.asScala.map(_.getType).contains(Schema.Type.RECORD)
case _ => false
}