gh-1476 - Fix regression in hashagg,local
gh-1476 - Fix regression in hashagg,local

A change in gh-1104, caused hashagg,local to fail with a serialization error

Signed-off-by: Jake Smith <b20121000db38205734e8ca1c74fe9668b08552a@lexisnexis.com>

afishbeck/HPCC-Platform,afishbeck/HPCC-Platform,afishbeck/HPCC-Platform,afishbeck/HPCC-Platform,afishbeck/HPCC-Platform,afishbeck/HPCC-Platform