HPCC-11997 ECLWatch should not auto-refresh archived WU pages

This fix removes the code for specifying auto-refresh values in
both WsWorkunits.WUInfo response and FileSpray.GetDFUWorkunit
response for archived WU. Without the value, both ECL WU page and
DFU WU page will not do auto-refresh in legacy ECLWatch.

Signed-off-by: wangkx <kevin.wang@lexisnexis.com>
Merge pull request #6292 from wangkx/h11997

HPCC-11997 ECLWatch should not auto-refresh archived WU pages

Reviewed-by: Gavin Halliday <ghalliday@hpccsystems.com>