CB-18629 - Data Lake Postgres upgrade fails due to flow restart

[pdarvasi]

This commit:

• eliminates the resourceid being 0 for a couple of flows in flowlog entity
• sets DBStackService as ResourceIdProvider
• introduces UpgradeDatabaseResponse that includes a flowIdentifier, currentVersion and a reason if the flow is not triggerable due to a certain validation
• removes BadRequest when upgrade flow is already happening -> just returns the flowId and a descriptive reason field
• introduces a check if the DB engine version matches the one sent in the request, and if so then it does not trigger the upgrade flow -> just returns the current version and a descriptive reason field