Use old style generics

Author: NickCao

packages/jumpstarter-kubernetes/jumpstarter_kubernetes/list.py

@@ -1,11 +1,13 @@
-from typing import Literal
+from typing import Generic, Literal, TypeVar
 
 from pydantic import Field
 
 from .json import JsonBaseModel
 
+T = TypeVar("T")
 
-class V1Alpha1List[T](JsonBaseModel):
+
+class V1Alpha1List(JsonBaseModel, Generic[T]):
     """A generic list result type."""
 
     api_version: Literal["jumpstarter.dev/v1alpha1"] = Field(alias="apiVersion", default="jumpstarter.dev/v1alpha1")