fix(mm): json schema for UnknownModelConfig again

Author: psychedelicious

invokeai/backend/model_manager/config.py

@@ -292,7 +292,7 @@ def parse(cls, mod: ModelOnDisk) -> dict[str, Any]:
 
     @staticmethod
     def json_schema_extra(schema: dict[str, Any]) -> None:
-        schema["required"] = list(set(schema["required"].extend(["key", "base", "type", "format"])))
+        schema["required"].extend(["key", "type", "base", "format"])
 
     model_config = ConfigDict(validate_assignment=True, json_schema_extra=json_schema_extra)