Create a version of MultimodalQnA example with Zilliz/Milvus as Vector DB

[codingjaguar]

Priori### Description

Create a version of MultimodalQnA example with Milvus as Vector DB

The implementation can reference this code example for the interaction with Milvus vector database: https://milvus.io/docs/multimodal_rag_with_milvus.md

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