DomainFrequencyExtractor should remove WWW prefix

[ruebot]

Currently the DomainFrequencyExtractor does not remove the WWW prefix. We should include RemovePrefixWWWDF as well.

aut/src/main/scala/io/archivesunleashed/app/DomainFrequencyExtractor.scala

Lines 30 to 38 in 9b1aae9

	def apply(d: DataFrame): Dataset[Row] = {
	val spark = SparkSession.builder().master("local").getOrCreate()
	// scalastyle:off
	import spark.implicits._
	// scalastyle:on
	d.groupBy(ExtractDomainDF($"url").as("domain"))
	.count()
	.sort($"count".desc)
	}