Currently, parse_conn_str is implemented in VERY similar manner in utils.py and in base_handler.py

One of these is for the data-plane ServiceBusAdministration code, the other is for the data-plane itself (servicebusclient and family.)

They can likely be combined significantly to reduce code duplication and improve maintainability.

In addition to this, _create_credential_from_connection_string_parameters is a VERY strange flow right now in order to provide sync vs async dispatch of the credential objects, coupling their respective implementation to the corrosponding sync or async handler. If there's a clever way to move this all into utils we're game for improvements in this space. (Considered using a functional callback to pass in the respective sync or async credential builder as a param to the create_credential function, but that seemed like a lateral move at best.)