Add MongoDB as a vector database

[rajeshvinayagam-lab]

In addition to other Vector Stores, can MongoDB be added as another vector store

[S1LV3RJ1NX]

Users can add a new vectorstore by inheriting from the base vector class, would love to have your contribution for the same.

[rajeshvinayagam-lab]

Sure have started working on the mongodb as a vector database will raise a pull request soon with the changes