[CDAP-20943] Use a separate consumer id for MetadataConsumerSubscriberService

[itsankit-google]

JIRA: CDAP-20943

Tested:

cdap=> select namespace,application,version,program_type,program,run from workflows where run in ('10a248d2-b9ee-11ee-b5d4-e6adf015ef44', '0cbdef44-b9d9-11ee-a8a2-6e00dd568637');
 namespace |     application      |               version                | program_type |       program        |                 run                  
-----------+----------------------+--------------------------------------+--------------+----------------------+--------------------------------------
 default   | DataFusionQuickstart | fe668473-b9d8-11ee-9046-6e00dd568637 | WORKFLOW     | DataPipelineWorkflow | 0cbdef44-b9d9-11ee-a8a2-6e00dd568637
 default   | DataFusionQuickstart | fe668473-b9d8-11ee-9046-6e00dd568637 | WORKFLOW     | DataPipelineWorkflow | 10a248d2-b9ee-11ee-b5d4-e6adf015ef44
(2 rows)

[tivv]

Note that we would need to see what does this change mean for upgrade cases. I am not sure if "new" consumer will read all messages for last 7 days or will start fresh (and potentially skip anything unprocessed). If latter, it may miss some messages during upgrade, should not be a bit issue as it's for lineage and anyway previous code misses messages.