[FR]: Core - API - Item Categories Interface Testing

### Software Core API ### Describe what you'd like to see As per the parent issue, need to comprehensively test the Item Categories REST interface Endpoints: - [ ] `GET` `/api/v1/db/{oqmDbIdOrName}/inventory/item-category`: - [ ] happy path (no categories) - [ ] happy path (categories) - [ ] Update openapi details - [ ] `POST` `/api/v1/db/{oqmDbIdOrName}/inventory/item-category`: - [ ] happy path - [ ] Unhappy path (invalid data) - [ ] Update openapi details - [ ] `GET` `/api/v1/db/{oqmDbIdOrName}/inventory/item-category`: - [ ] happy path (no categories) - [ ] happy path (categories) - [ ] Update openapi details ... more / the rest of the Item Categories endpoints ### Is your feature request related to a problem? _No response_ ### Describe alternatives you've considered None ### Additional context None