HPCC-8815 Remove deserializer from getDictionaryResult

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>
Merge pull request #3977 from ghalliday/issue8815

HPCC-8815 Remove deserializer from getDictionaryResult

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>