SerializerMutation don't excluded write_only fields

[vladimirmyshkovski]

class UserSerializer(ModelSerializer):

    class Meta:
        model = User
        fields = ['username', 'name', 'first_name', 'last_name', 'email', 'password']
        read_only_fields = ['username']
        extra_kwargs = {'password': {'write_only': True}}


class UserSerializerMutation(SerializerMutation):

    class Meta:
        lookup_field = 'username'
        serializer_class = UserSerializer

It is expected that the password will not be possible to get as a result.

[kamilkijak]

It's related to #385, there is no support for read_only_fields and write_only_fields yet.