Provide ability to have a single data warehouse instance shared across multiple organisations

[cbryanreapit]

Background context We should ensure that it is possible to have a single data warehouse compute resource that can be shared across multiple organisations. Likely ties in with the organisation group work.

Specification

• Update POST customers endpoint to capture the additional customer Ids that the resulting warehouse will be shared between
• Continue to capture the 'lead' customer in same way as present, additional customers would be an optional field
• Record a customers entity in such a way that it can be shared amongst all organisations specified (single customer entity serving multiple organisations)
• Need to ensure user / share operations work regardless of which organisation you're logged in behalf of
• May need to record the name of the snowflake share against an entity for above to work

[HollyJoyPhillips]

PL, RW & HP: Reviewed