getMap on BYOC layer using WMS doesn't work

[dgostencnik]

This issue has been brought up on AM project where expert-app was using timelapse component with PlanetData without authentication.

There are 2 reasons why BYOCLayer wms getMap request doesn't work

• BYOCLayer.getMap is always calling updateLayerFromServiceIfNeeded which requires auth
• BYOCLayer.getShServiceHostname() requires locationId which can be only be obtained from collection metadata which requires auth

I think updateLayerFromServiceIfNeeded could be ommited for non-authenticated WMS requests and some sort of default location based on serviceUrl could be provided.