Fixes #86615 by changing the way we check if we can remove persistent layers. Instead of depending on the layer's authId to be null (which with old or erroneus layers might not be), we set in the process of loading public layers for the admin a publicLayer:true property in the layer's metadata.
Merge pull request #218 from luisromangz/86615-PersistentRemovalOfPublicLayers

#86615 persistent removal of public layers