Make ListProviderScanner Scanner Less verbose

Each time you reload the admin ui and create a new event the ListProviderScanner will tell that there are lists:

12:05:57 INFO (ListProvidersScanner$SingleResourceListProviderImpl:119) - Getting list LANGUAGES query org.opencastproject.index.service.resources.list.query.ResourceListQueryImpl@48f620c7 org null
12:05:57 INFO (ListProvidersScanner$SingleResourceListProviderImpl:119) - Getting list LICENSES query org.opencastproject.index.service.resources.list.query.ResourceListQueryImpl@31de6e62 org null
12:05:57 INFO (ListProvidersScanner$SingleResourceListProviderImpl:119) - Getting list LANGUAGES query org.opencastproject.index.service.resources.list.query.ResourceListQueryImpl@299a4e05 org null
12:05:57 INFO (ListProvidersScanner$SingleResourceListProviderImpl:119) - Getting list LICENSES query org.opencastproject.index.service.resources.list.query.ResourceListQueryImpl@12632e42 org null

It should be sufficient to have these as debug logs.