FeedIterator.ReadNextAsync() returns ErrorMessage with expired resourceToken

[fuocor]

Describe the bug
I am not sure this is a bug but...
When calling FeedIterator.ReadNextAsync() with an expired/used ResourceToken the StatusCode == HttrpStatusCode.Forbidden and the content has

{"_rid":"LkF8AJd9jCE=","Documents":[],"_count":0}

and an ErrorMessage of:

Message: {"Errors":["Request is blocked. Please check your authorization token and Cosmos DB account firewall settings."]}ActivityId: b55cd9f7-3571-4846-aae1-7145b21d76ad, Request URI: /apps/DocDbApp/services/DocDbServer21/partitions/a4cb4961-38c8-11e6-8106-8cdcd42c33be/replicas/1p/, RequestStats: {"responseStatisticsList":[{"RequestResponseTime":"2019-11-20T19:38:55.3835348Z","StoreResult":{"LSN":2140,"QuorumAckedLSN":2140,"GlobalCommittedLSN":-1,"NumberOfReadRegions":0,"ItemLSN":-1,"SessionToken":{"LSN":2140},"UsingLocalLSN":true,"RequestCharge":0.0,"CurrentReplicaSetSize":1,"CurrentWriteQuorum":-1,"IsValid":true,"IsGoneException":false,"IsNotFoundException":false,"IsInvalidPartitionException":false,"StorePhysicalAddress":"rntbd://127.0.0.1:10253/apps/DocDbApp/services/DocDbServer21/partitions/a4cb4961-38c8-11e6-8106-8cdcd42c33be/replicas/1p/","IsClientCpuOverloaded":false},"RequestResourceType":2,"RequestOperationType":15}],"supplementalResponseStatisticsList":[],"addressResolutionStatistics":{},"ContactedReplicas":[],"FailedReplicas":[],"RegionsContacted":["https://127.0.0.1:8081/"],"RequestLatency":"00:00:00.3219483","IsCpuOverloaded":false}, SDK: Windows/10.0.17763 cosmos-netstandard-sdk/3.3.0

My question is that just about everywhere else in the SDK the messages seem to get pushed into the response content and headers. Is this by design?

Environment summary
SDK Version: Source
OS Version Windows 10

Additional context
Add any other context about the problem here (for example, complete stack traces or logs).

[j82w]

This is a bug. I have a PR out with the fix. The content will be null on failure.