`distinguisherMethod` defines how to compute the flow distinguisher for requests that match this schema. `nil` specifies that the distinguisher is disabled and thus will always be the empty string.

`matchingPrecedence` is used to choose among the FlowSchemas that match a given request. The chosen FlowSchema is among those with the numerically lowest (which we take to be logically highest) MatchingPrecedence. Each MatchingPrecedence value must be ranged in [1,10000]. Note that if the precedence is not specified, it will be set to 1000 as default.

`priorityLevelConfiguration` should reference a PriorityLevelConfiguration in the cluster. If the reference cannot be resolved, the FlowSchema will be ignored and marked as invalid in its status. Required.

`rules` describes which requests will match this flow schema. This FlowSchema matches a request if and only if at least one member of rules matches the request. if it is an empty slice, there will be no requests matching the FlowSchema.