all vestiges of ldm.invoke removed

invokeai/app/invocations/prompt.py

@@ -1,9 +1,13 @@
 from typing import Literal
+
 from pydantic.fields import Field
+
 from .baseinvocation import BaseInvocationOutput
 
+
 class PromptOutput(BaseInvocationOutput):
     """Base class for invocations that output a prompt"""
-    type: Literal['prompt'] = 'prompt'
+
+    type: Literal["prompt"] = "prompt"
 
     prompt: str = Field(default=None, description="The output prompt")