Minor schema validation error: doesn't complain about invalid default for null and file types

Describe the bug
NoneProperty.build and FileProperty.build do have logic to detect if a default other than None was provided for a null property, or if any default was provided for a binary string—and we do have unit tests for those. However, in reality NoneProperty.build and FileProperty.build do not actually get called, because property_from_data just calls the initializers directly instead. Therefore if you do something like this, the default is simply ignored.

OpenAPI Spec File

components:
  schemas:
    MyModel:
      properties:
        myNullProperty:
          type: "null"
          default: "definitely not null"
        myBinaryString:
          type: string
          format: binary
          default: "???"

Desktop (please complete the following information):

• OS: any
• Python Version: any
• openapi-python-client version: 0.21.6

Comece rastreando property_from_data e compare suas chamadas diretas ao inicializador com NoneProperty.build e FileProperty.build, que já contêm lógica de validação. Execute os testes unitários existentes para esses builders e, em seguida, adicione cobertura mostrando que os valores padrão inválidos nos schemas OpenAPI fornecidos são rejeitados em vez de ignorados.