bug: System.NullReferenceException in Topic Reader #528
Description
System.NullReferenceException: Object reference not set to an instance of an object.\n
at Ydb.Sdk.Services.Topic.Reader.ReaderSession`1.StopPartitionSessionRequest(StopPartitionSessionRequest stopPartitionSessionRequest)\n
at Ydb.Sdk.Services.Topic.Reader.ReaderSession`1.RunProcessingStreamResponse()