Properties of a ParameterInfo.
Properties:
| Name | Type | Attributes | Description | 
|---|---|---|---|
| displayName | string | null | <optional> | ParameterInfo displayName | 
| required | boolean | null | <optional> | ParameterInfo required | 
| state | google.cloud.dialogflow.cx.v3beta1.PageInfo.FormInfo.ParameterInfo.ParameterState | null | <optional> | ParameterInfo state | 
| value | google.protobuf.IValue | null | <optional> | ParameterInfo value | 
| justCollected | boolean | null | <optional> | ParameterInfo justCollected |