* add test case for Chroma save/load
* minor name change
* add delete_collection support for chroma
* move save load to chroma
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Co-authored-by: Nguyen Trung Duc (john) <john@cinnamon.is>
Design the base interface of vector store, and apply it to the Chroma Vector Store (wrapped around llama_index's implementation). Provide the pipelines to populate and retrieve from vector store.