chroma: fix persistence if client_settings is passed in (#25199)

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Co-authored-by: Erick Friis <erick@langchain.dev>
Co-authored-by: Chester Curme <chester.curme@gmail.com>

libs/partners/chroma/langchain_chroma/vectorstores.py

@@ -318,6 +318,9 @@ class Chroma(VectorStore):
                 client_settings.persist_directory = (
                     persist_directory or client_settings.persist_directory
                 )
+                client_settings.is_persistent = (
+                    client_settings.persist_directory is not None
+                )
 
                 _client_settings = client_settings
             elif persist_directory: