HPCC-11763 Docs: add --version to DFUPlus

Signed-off-by: Jim DeFabia <jamesdefabia@lexisnexis.com>
Merge pull request #6416 from JamesDeFabia/11763Add_version_actionToDFUPlusDocs

HPCC-11763 Docs: add --version to DFUPlus

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>