Error codes for Settlements

[elnyry-sam-k]

Goal:

Note: As the Error Framework was being implemented for central-settlement, the aspect of using Scheme specific or Settlement specific error code came up. I think Settlements needs something like a 6xxx series of errors that can be used for Settlements and this needs to be standardized.
PR in context - mojaloop/central-settlement#83

Tasks:

• TBD [ @? ]

Acceptance Criteria:

• Designs are up-to date
• Unit Tests pass
• Integration Tests pass
• Code Style & Coverage meets standards
• Changes made to config (default.json) are broadcast to team and follow-up tasks added to update helm charts and other deployment config.
• TBD

Pull Requests:

• TBD

Follow-up:

• N/A

Dependencies:

• N/A

Accountability:

• Owner: TBC
• QA/Review: TBC