Description
Comments and whitespace filtering has been performed by uniVocity parser already according to parser settings:
https://github.com/apache/spark/blob/branch-2.3/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/csv/CSVOptions.scala#L178-L180
It is not necessary to do the same before parsing. Need to inspect all places where the filterCommentAndEmpty method is called, and remove the former one if it duplicates filtering of uniVocity parser.