General improvements to MQTT5 canary

[TwistedTwigleg]

Description of changes:

Makes the following improvements to the MQTT5 canary:

• Allows running the MQTT5 canary forever if the seconds to run is set to 0
• Allows setting the port for the Canary to use via -p <port> or --port <port>
• Adds an ACK timeout for the operations and callbacks for publish, subscribe, and unsubscribe that will print the error code should an error occur

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov-commenter]

Codecov Report

Patch coverage has no change and project coverage change: +0.08 :tada:

Comparison is base (137c31c) 82.16% compared to head (9f90237) 82.24%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #252 +/- ## ========================================== + Coverage 82.16% 82.24% +0.08% ========================================== Files 16 16 Lines 7155 7154 -1 ========================================== + Hits 5879 5884 +5 + Misses 1276 1270 -6 ``` [see 1 file with indirect coverage changes](https://codecov.io/gh/awslabs/aws-c-mqtt/pull/252/indirect-changes?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=awslabs) Help us with your feedback. Take ten seconds to tell us [how you rate us](https://about.codecov.io/nps?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=awslabs). Have a feature suggestion? [Share it here.](https://app.codecov.io/gh/feedback/?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=awslabs)

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[TwistedTwigleg]

Thanks! Merging into main...