fix: add remove chroma cache

vector_store.py

@@ -1,4 +1,5 @@
 import streamlit as st
+import chromadb
 from langchain_huggingface import HuggingFaceEmbeddings
 from langchain_chroma import Chroma
 from langchain_community.document_loaders import PyPDFLoader
@@ -22,6 +23,7 @@ def load_vector_store():
     load vector store on every page load
     """
     model = load_embedding_model("sentence-transformers/all-MiniLM-L6-v2")
+    chromadb.api.client.SharedSystemClient.clear_system_cache()
     vector_store = Chroma(
         collection_name="main_store",
         embedding_function=model,