[ServiceBus/EventHub] move async ssl opts to transport constructor

[swathipil]

addresses: #37246

Creating the SSLContext and loading verify locations can be done in the constructor. Moving the check to the constructor so it doesn't need to be run in a ThreadPoolExecutor.

TODO:

• test/confirm
  • test_sb_client_async.py:test_custom_endpoint_connection_verify_exception_async
  • test_negative_async.py:test_client_invalid_credential_async

[swathipil]

/azp run python - eventhub - tests

[swathipil]

/azp run python - servicebus - tests

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[azure-sdk]

API change check

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[l0lawrence]

lgtm :)

[sveinse]

Is it an acceptable solution to move blocking IO to the constructor of the class? A common use case of these objects is to dynamically create ServiceBusClient instances from coroutines which is under a running async event loop. Any blocking IO during initialization will restrict when and where in an async app these objects can be created, which I believe is limiting the usefulness of the fix. Thank you.

(I'm the reporter for the issue #37246)

[swathipil]

Hi @sveinse - We will discuss and let you know. Thanks.

[sveinse]

@swathipil thank you. If you're not aware of the comments in #37246 , please consider the new comments #37246 (comment) and onwards. Thanks.