Legal API - Remove complianceWarnings list property in business resource returned from GET business endpoint

As a part of the original work to refactor the legal api business endpoint, a generic warnings list with a warningType property for each warning item in the list was introduced to replace the complianceWarning list property. To allow the UIs to integrate independent of the timing of the rollout of the BE changes, the complianceWarning property was left in place. Now that the FE has integrated these changes in #12300, the complianceWarnings list property can be removed from the business resource returned. There are also some other misc updates that will need to be made in the BE to remove existing compliance warnings related code.

**TODOs**
- [ ] Remove complianceWarnings population logic from being returned for GET business endpoint
- [ ] Remove complianceWarnings related(property getter/setter, json function etc) from business model
- [ ] Address TODOs in original [PR](https://github.com/bcgov/lear/pull/1533)
- [ ] Updates tests as required

Review the original PR #1533 and the GET business endpoint first, then trace the business model's complianceWarnings handling. Remove the listed population and model-related pieces, address the PR TODOs, and update the affected tests so the endpoint no longer returns complianceWarnings.

Written by the indexing model from the issue text.