Don't throw an exception if we run into trouble while cleaning existing temp content for provider

We recently introduced an API where the existing content (if any) of a temp provider would be cleaned up while creating a new temp provider for a specific type. This new API  was implemented to throw an exception if something goes wrong when *triggering* a cleanup of the existing content. That previous implementation has shown that it can lead to an undesired behaviour of causing the server boot to fail.

The commit here changes the implementation to just log a message instead of throwing an error in such cases.