Changes to POST /v2/favorites

added EntryDescriptionRequiredError OneLineError to the errors/items/error response property anyOf list for the response status 422

added HasToBeActiveError ProjectNotSelectedError ServiceIsNotAllowedError ProjectBookingIsProhibitedForIntervalProjectsError SubprojectNotSelectedError AddingEntriesNotAllowedError to the errors/items/error response property anyOf list for the response status 422

endpoint added