Add integration tests for connecthealth

[Alan4506]

Description of Changes

This PR adds integration tests for the Connect Health service client (aws-sdk-connecthealth), covering the following:

• Non-streaming operations: create_domain, list_domains, get_domain, delete_domain, create_subscription, list_subscriptions, get_subscription, deactivate_subscription, get_medical_scribe_listening_session.
• Bidirectional event streaming operation: start_medical_scribe_listening_session.

The test structure and patterns follow the same conventions established in the Lex Runtime V2 integration tests (PR #51), such as session-scoped conftest fixtures for resource setup/teardown.

Testing

The integration tests create real AWS resources (Domain, Subscription, S3 bucket) under the calling AWS identity, run a live streaming session against the Connect Health service, then delete those resources. The calling identity therefore needs Admin (or equivalent) permissions on ConnectHealth and S3.

1. Assume an Admin role and export the resulting credentials so the new SDK (which uses EnvironmentCredentialsResolver) can pick them up:

   export AWS_ACCESS_KEY_ID=...
   export AWS_SECRET_ACCESS_KEY=...
   export AWS_SESSION_TOKEN=...

2. From clients/aws-sdk-connecthealth/, install the client and test dependencies:

   uv pip install -e . --group test

3. Run the tests

   python -m pytest tests/

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[SamRemis]

[nit]

Two separate http calls means we could create the bucket but fail to tag it. We can include tags on the initial request via CreateBucketConfiguration. See the docs for the syntax.

[Alan4506]

Thanks! Addressed in 62eb957.

[SamRemis]

[nit/question]

Did we consider using asyncio.timeout here? Something like this:

          async with asyncio.timeout(_SUBSCRIPTION_POLL_TIMEOUT_SECONDS):
              while True:
                  response = await client.get_subscription(
                      input=GetSubscriptionInput(
                          domain_id=domain_id, subscription_id=subscription_id
                      )
                  )
                  if (
                      response.subscription is not None
                      and response.subscription.status == SubscriptionStatus.INACTIVE
                  ):
                      return
                  await asyncio.sleep(_SUBSCRIPTION_POLL_INTERVAL_SECONDS)

IMO that's a little more readable and effectively the same, but it's personal preference. Though the above will cancel a request while it's in flight, and the existing code always finishes the given iteration.

[Alan4506]

Thanks for the suggestion! I considered asyncio.timeout, but I'd lean towards keeping the current approach. As you noted, it always finishes the given iteration rather than cancelling it mid-request, which feels a bit safer.

That said, on a related comment in another PR we did switch from asyncio.get_event_loop() to asyncio.get_running_loop(). So I also applied the switch for this PR in 62eb957. In this case, it also keeps things consistent with the other existing tests.

[SamRemis]

[minor nit]
This confused me a bit since this isn't a streaming operation, but it still uses the streaming endpoint. Maybe naming it streaming_endpoint_plugin would be easier to read, but this one is really not that big of a deal.

[Alan4506]

Thanks, agreed there's some confusion here. However, naming it streaming_endpoint_plugin directly would shadow the imported function of the same name and cause an UnboundLocalError on the following line:

streaming_endpoint_plugin = streaming_endpoint_plugin(REGION)

so I renamed it to endpoint_plugin instead to reduce the confusion. Done in 62eb957.