Feature request: Add support for basic authentication when connecting with external opensearch cluster

[saeedahmedinit]

Hello, First of all thank you very much for providing photon. It is very cool to work with it. We have a use case in our k8s environment where we want to connect photon to an external opensearch. Unfortunately we cannot bypass opensearch authentication in production. Would you be open to introduce atleast basic authentication when connect photon to an external opensearch?

Thank you very much!

[lonvia]

Sure, happy to take a PR on that.