Test how large payload is handled.

1. Call a method with a payload that will exceed the maximum payload supported by the implementation for CommandService.{cmd,cmd_args} or`GrpcService.payloads`` or both, such as adding a large number of static routes. If the implementation supports configuration of this limit, it may be configured to artificially reduce the limit for easier testing.
2. Establish gNSI connection to the DUT.
   1. Call gnsi.acctz.v1.Acctz.RecordSubscribe with RecordRequest.timestamp = T1. T1 should be timestamp that covers the above gNMI SET action.
   2. Verify that The appropriate boolean should be set; one of CommandService.{cmd_istruncated,cmd_args_istruncated} or GrpcService.payload_istruncated.
   3. If an RPC, the contents of the payload field(s) is structured and must remain syntactically parsable.

The below yaml defines the OC paths intended to be covered by this test. OC paths used for test setup are not listed here.

TODO(OCRPC): Record may not be complete

paths:
    # Accounting does not currently support any telemetry; see https://github.com/openconfig/gnsi/issues/97 where it might become /system/aaa/acctz/XXX
rpcs:
  gnsi:
    acctz.v1.Acctz.RecordSubscribe:

vRX