Add an integration test for drain

[jhendrixMSFT]

• [ ] The purpose of this PR is explained in this or a referenced issue.
• [ ] Tests are included and/or updated for code changes.
• [ ] Updates to CHANGELOG.md are included.
• [ ] MIT license headers are included in each file.

[jhendrixMSFT]

It appears that the fix for this in https://github.com/Azure/azure-amqp/issues/219 has regressed.

[jhendrixMSFT]

Opened https://github.com/Azure/azure-amqp/issues/243 to track it.

[jhendrixMSFT]

Closing as we're removing this API for now.