Change template to private attribute and simplify imports (#101)

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Co-authored-by: ian <ian@cinnamon.is>

knowledgehub/llms/prompts/base.py

@@ -1,6 +1,7 @@
 from typing import Callable, Union
 
-from ...base import BaseComponent, Document
+from kotaemon.base import BaseComponent, Document
+
 from .template import PromptTemplate
 
 
@@ -16,6 +17,7 @@ class BasePromptComponent(BaseComponent):
 
     class Config:
         middleware_switches = {"theflow.middleware.CachingMiddleware": False}
+        allow_extra = True
 
     def __init__(self, template: Union[str, PromptTemplate], **kwargs):
         super().__init__()