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

まず property_from_data を追跡し、その直接的な initializer 呼び出しを、すでに検証ロジックを含んでいる NoneProperty.build および FileProperty.build と比較します。これらの builder に対する既存の unit test を実行し、提供されている OpenAPI スキーマの無効なデフォルト値が無視されるのではなく拒否されることを示すカバレッジを追加します。