type indicates whether this priority level is subject to limitation on request execution.
A value of "Exempt" means that requests of this priority level are not subject to a limit (and thus are never queued) and do not detract from the capacity made available to other priority levels.
A value of "Limited" means that (a) requests of this priority level are subject to limits and (b) some of the server's limited capacity is made available exclusively to this priority level.
Required.
PriorityLevelConfigurationSpec specifies the configuration of a priority level.