Test flake: `serial console can connect while starting`

[david-crespo]

trace.zip

https://github.com/oxidecomputer/console/actions/runs/14268575601/job/39996289244

This one is really not a big deal — I think the instance is just starting slightly too fast, so we're missing the starting message when we look for it.

[david-crespo]

Ok, now we got it in Safari. My current guess is that this is due to performance improvements in React 19.1, which I bumped 3 commits ago in f52f50c.

https://github.com/oxidecomputer/console/actions/runs/14269558670/job/39999451085

[david-crespo]

This is driving me nuts in #2833. Will want to take a look soon.

[david-crespo]

Not fixed! https://github.com/oxidecomputer/console/actions/runs/16033717171/job/45240331757