Intel OPEA integration

Contribute use-case:

• RAG example: https://github.com/opea-project/GenAIExamples/tree/main/ChatQnA

The above depends on a couple of services in: https://github.com/opea-project/GenAIComps/tree/main/comps/

• define database service (MariaDB Vector)
• define receiver service (The vector search abstraction)
• define dataprep service (The vector storing abstraction)