Basic Auth support for Java client

I'm starting to secure my pinot set up and I'm not able to find the way in the official Java client to add my auth token. According to @mayankshriv it is not supported.

For now as a work around I'm using the API to perform queries but it would be nice to have access to auth also from the Java client.

Start by locating the official Java client entry point and the existing API query path, then check how requests currently carry authentication information. The work is done when the Java client accepts the requested auth token or Basic Auth credentials and authenticated queries work through the client; no specific file or test is named in the issue.

Written by the indexing model from the issue text.