Two missing fields in projection payloads

[galeaspablo]

Projections payloads do not have the fields:

• data_source_description
• data_destination_description

as per the docs

{
  "data_source_id": "AMBAR-51f161c7-faef-4b3b-9149-32e1ae8a03af",
  "data_source_description": "postgres production data source", # this is missing
  "data_destination_id": "AMBAR-d7f5c446-1e79-4f5c-82ed-afe3beceb144",
  "data_destination_description": "concurrent visitors per page", # this is missing
  "payload": {...}
} 

[galeaspablo]

Please only work on this once #12 is done (and before serverless)