HPCC-11602 Fix issues with csv test and csv reading of newlines

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>
Merge pull request #6030 from ghalliday/issue11602

HPCC-11602 Fix issues with csv test and csv reading of newlines

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>