MultiModalVectorStoreIndex from a ChromaDB collection containing text and image nodes, It ignores the imageNodes. However If I instanciate a VectorStoreIndex using the same nodes or documents it's correctly retrieving the image nodes. I suppose that it's a bug ?MultiModalVectorStoreIndex based on an in-memory ChromaDB instance. I'm using an AzureOpenAI embedding model and I would like to understand why when I'm retrieving my nodes using as_retriever().retrieve(...), all the retrieved nodes have null embeddings value. I've checked that the related chroma db collection is containing embeddings value (using chroma_collection.query method )