Spring generator not including UniqueElements annotation

Description

When the openapi has the uniqueItems: true on an array it does not set @UniqueElements on the code

Swagger-codegen version

3.0.19

Swagger declaration file content or url

If you post the code inline, please wrap it with

openapi: 3.0.0
info:
  title: Concierge
  version: 1.0.0
  description: Concierge API
  contact:
    name: data-stack
    email: data-stack@truphone.com
servers:
  - url: 'http://localhost:8080'
    description: local
paths:
  /foo:
    get:
      summary: Your GET endpoint
      tags: []
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/FooObject'
components:
  schemas:
    FooObject:
      title: FooObject
      type: object
      properties:
        sources:
          type: array
          uniqueItems: true
          items: 
            type: string

Command line used for generation

swagger-codegen generate -i docs/contract.yml -l spring -o ./

Reproduce the issue with the supplied OpenAPI schema and the swagger-codegen generate -i docs/contract.yml -l spring -o ./ command. Trace the Spring generator's handling of uniqueItems: true for the sources array, then verify that the generated model includes @UniqueElements.