This patch moves the BlockingErrorCode table and the
IsClassifierBlockingErrorCode / IsClassifierBlockingEventCode /
GetClassifierBlockingEventCode / ClassifierBlockingErrorCodeToConsoleMessage
helpers from UrlClassifierFeatureFactory into ChannelClassifierUtils so the
latter no longer needs to depend on UrlClassifierFeatureFactory.h.
Differential Revision: https://phabricator.services.mozilla.com/D301722