test(iroh): Make test_relay_datagram_queue less timing dependent

[matheus23]

Description

I've seen test_relay_datagram_queue fail on windows recently: https://github.com/n0-computer/iroh/actions/runs/12669553316/job/35307313406

Given that

• when the test failed, it took 720ms,
• when the test succeeded, it took 150ms and 320ms,
• we've got a 100ms timeout on one of the futures, and
• the tokio scheduler (I think) doesn't optimize for average job time,

I'm not convinced there's a race condition.

So, instead I'm rewriting the test to be less timing-dependent. And less confusing as well and have better logging.

Change checklist

• Self-review.
• Documentation updates following the style guide, if relevant.
• Tests if relevant.
• All breaking changes documented.

[github-actions]

Documentation for this PR has been generated and is available at: https://n0-computer.github.io/iroh/pr/3106/docs/iroh/

Last updated: 2025-01-08T16:55:05Z

[github-actions]

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Last updated for commit: d33826a