[ServiceBus] Ensure exceptions are idiomatic, properly named, and non-spurious.

[KieranBrantnerMagee]

Consider this issue "let's triage any well defined exception oddities we've found." An (incomplete) list below:

• [x] Mode being passed as wrong type should be a TypeError (MessageHandlerError out of UAMQP)
• [x] should (do?) all custom exception types have the ServiceBus* prefix?
• [x] VendorLinkDetatch failures when terminating SessionPool samples

  
  Traceback (most recent call last):
  File "C:\Users\kibrantn\Source\Repos\azure-sdk-for-python-kibrantn\sdk\servicebus\azure-servicebus\azure\servicebus\aio\_base_handler_async.py", line 118, in _do_retryable_operation
  return await operation(**kwargs)
  File "C:\Users\kibrantn\Source\Repos\azure-sdk-for-python-kibrantn\sdk\servicebus\azure-servicebus\azure\servicebus\aio\_servicebus_receiver_async.py", line 169, in _open
  while not await self._handler.client_ready_async():
  File "C:\Users\kibrantn\Source\Repos\azure-sdk-for-python-kibrantn\sdk\servicebus\sb_t2_env\lib\site-packages\uamqp\async_ops\client_async.py", line 362, in client_ready_async
  if not await self._client_ready_async():
  File "C:\Users\kibrantn\Source\Repos\azure-sdk-for-python-kibrantn\sdk\servicebus\sb_t2_env\lib\site-packages\uamqp\async_ops\client_async.py", line 817, in _client_ready_async
  if self.message_handler.get_state() == constants.MessageReceiverState.Error:
  File "C:\Users\kibrantn\Source\Repos\azure-sdk-for-python-kibrantn\sdk\servicebus\sb_t2_env\lib\site-packages\uamqp\receiver.py", line 262, in get_state
  raise self._error
  uamqp.errors.LinkDetach: ErrorCodes.NotAllowed: A sessionful message receiver cannot be created on an entity that does not require sessions. Ensure RequiresSession is set to true when creating a Queue or Subscription to enable sessionful behavior. TrackingId:4fd16b9a-30a9-4115-93ad-3ebbdf9e921d_B18, SystemTracker:kibrantn-azure-sdk-test:Queue:test, Timestamp:2020-05-01T05:49:40 TrackingId:7bf09bd4b08142a4baef26ad2ac9104a_G27, SystemTracker:gateway7, Timestamp:2020-05-01T05:49:40

[KieranBrantnerMagee]

1. Mode has been fixed within SB.
2. Design discussion was had regarding these signatures, we're apt to add a prefix for items where cross-SDK verbiage exists (ala MessageError). Task has been created to do this work Here.
3. Problem diagnosed, intentional design choice in UAMQP to log this as warning. Proposed solution is a "known vendor failures" parameter to allow callers to declare certain failures not-needing-to-be-warned if they're handled or understood in the caller context. Task has been created within UAMQP here.