HPCC-10571 Add RemoveOwnedSubFiles to docs

Signed-off-by: JamesDeFabia <James.Defabia@LexisNexis.com>
Merge pull request #5309 from JamesDeFabia/10571_RemoveOwnedSubFilesDocs

HPCC-10571 Add RemoveOwnedSubFiles to docs

Reviewed-By: Jake Smith <jake.smith@lexisnexis.com>
Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>