HPCC-10287 - Catch subfiles have correct @num sequence

Also allow daliadmin checksuperfile to check and fix these cases

Signed-off-by: Jake Smith <jake.smith@lexisnexis.com>
Merge pull request #5102 from jakesmith/hpcc-10287_4.2

HPCC-10287 - Catch subfiles have correct @num sequence

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>