[servicebus] pylint issues

[l0lawrence]

• azure\servicebus_servicebus_client.py:45: [C4748(client-accepts-api-version-keyword), ServiceBusClient] The client constructor needs to take in an optional keyword-only api_version argument. https://azure.github.io/azure-sdk/python_design.html#specifying-the-service-version

• azure\servicebus\aio_servicebus_client_async.py:38: [C4748(client-accepts-api-version-keyword), ServiceBusClient] The client constructor needs to take in an optional keyword-only api_version argument. https://azure.github.io/azure-sdk/python_design.html#specifying-the-service-version

• azure\servicebus\amqp_constants.py:11: [C4747(enum-must-inherit-case-insensitive-enum-meta), AmqpMessageBodyType] The enum must inherit from CaseInsensitiveEnumMeta. https://azure.github.io/azure-sdk/python_implementation.html#extensible-enumerations

• azure\servicebus\management_api_version.py:9: [C4747(enum-must-inherit-case-insensitive-enum-meta), ApiVersion] The enum must inherit from CaseInsensitiveEnumMeta. https://azure.github.io/azure-sdk/python_implementation.html#extensible-enumerations

• azure\servicebus_common\constants.py:170: [C4747(enum-must-inherit-case-insensitive-enum-meta), ServiceBusReceiveMode] The enum must inherit from CaseInsensitiveEnumMeta. https://azure.github.io/azure-sdk/python_implementation.html#extensible-enumerations

• azure\servicebus_common\constants.py:174: [C4747(enum-must-inherit-case-insensitive-enum-meta), ServiceBusMessageState] The enum must inherit from CaseInsensitiveEnumMeta. https://azure.github.io/azure-sdk/python_implementation.html#extensible-enumerations

• azure\servicebus_common\constants.py:190: [C4747(enum-must-inherit-case-insensitive-enum-meta), ServiceBusSubQueue] The enum must inherit from CaseInsensitiveEnumMeta. https://azure.github.io/azure-sdk/python_implementation.html#extensible-enumerations

[l0lawrence]

working on this, just added as an fyi