Generated discriminator uses full path instead of relative

[Sholto]

For example, the following code

    AddVoucherResult:
      oneOf:
        - $ref: '#/components/schemas/AddVoucherSuccess'
        - $ref: '#/components/schemas/AddVoucherFailure'
      discriminator:
        propertyName: valid
        mapping:
          true: '#/components/schemas/AddVoucherSuccess'
          false: '#/components/schemas/AddVoucherFailure'

    AddVoucherFailure:
      type: object
      required:
        - valid
      properties:
        valid:
          type: boolean
        reasonForFailure:
          type: string

    VoucherValidationResult:
      type: object
      required:
        - valid
      properties:
        valid:
          type: boolean
        reasonForFailure:

Yields the following:

                discriminator:
                  propertyName: valid
                  mapping:
                    "true": /Users/sholto/Development/taxicharge-pass/api/frag/voucher.yml#/components/schemas/AddVoucherSuccess
                    "false": /Users/sholto/Development/taxicharge-pass/api/frag/voucher.yml#/components/schemas/AddVoucherFailure

As can be seen, the path is the full path location rather than the relative one that is used elsewhere.