Need to support multi type credentials such as STS credentials

[LindaSummer]

Reason

I found it becomes a little hard to connect from one eks cluster to another account's athena through STS role assumption. Static credentials may become expired after a priod.

Advise

I think it's better to give a closure in driver configuration like 'func() *session.Session' and call it before use ACCESS_KEY and SECRET to get session. This can support all aws sdk's credential types.