Make possible use values other than strings as discriminator

[maks56893]

Sometimes I should use boolean value as value for discriminator field. Now when generating union methods for this type I get types errors
Example schema

ConfigHttp:
  type: object
  properties:
    is_http:
      type: boolean
      enum: [true]
    host:
      type: string
    port:
      type: integer
ConfigSsh:
  type: object
  properties:
    is_http:
      type: boolean
      enum: [false]
    host:
      type: string
    key:
      type: string
ConfigSchema:
  oneOf:
  - $ref: "#/components/schemas/ConfigHttp"
  - $ref: "#/components/schemas/ConfigSsh"
  discriminator:
    propertyName: is_http
    mapping:
      false: "#/components/schemas/ConfigSsh"
      true: "#/components/schemas/ConfigHttp"

In result I get method like this. "false" value is don't fit here

func (t *ConfigSchema) FromConfigSsh(v ConfigSsh) error {
	v.IsHttp = "false"
	b, err := json.Marshal(v)
	t.union = b
	return err
}