text: Title: Why does Mixins with resolver not work with ModelSchema?
  Body: Please describe what you are trying to achieve
  
  I wanted to mix in resolver to ModelSchemas so I do not have to write them all the time.
  
  Please include code examples (like models code, schemes code, view function) to help understand the issue
  First define a Mixin class with resolver
  ```
  from pydantic import field_validator
  from appcore.services.utils import slugify
  
  class IdSerializerOutMixin:
      """
      Mixin to convert uuid4 to websafebase64 id to be used in the response
      """
  
      id: str
  
      @staticmethod
      def resolve_id(obj):
          return slugify(obj.id)
  ```
  
  This works
  ```
  from ninja import ModelSchema
  from appcore.serializers.commons import IdSerializerOutMixin
  from appcore.services.utils import slugify
  from appstore.models.collections import Collection
  
  
  class CreateCollectionPostOut(ModelSchema):
      id: str
  
      class Meta:
          model = Collection
          exclude = ["user"]
  
      @staticmethod
      def resolve_id(obj):
          return slugify(obj.id)
  ```
  This does not work
  ```
  from ninja import ModelSchema
  from appcore.serializers.commons import IdSerializerOutMixin
  from appcore.services.utils import slugify
  from appstore.models.collections import Collection
  
  
  class CreateCollectionPostOut(ModelSchema, IdSerializerOutMixin):
      class Meta:
          model = Collection
          exclude = ["user"]
  ```
  
  Thanks!