fix(qemu): improve logging, make connection check less spammy

[89luca89]

This improves a bit the logging, making it less noisy and adhere to other runners' output.
Also, improve a bit the connection check, which gets very spammy on less performant machines (or cross compiles) where IO timeout was set way too low.

[89luca89]

The Test fail seems related to numpy:

2024/12/13 18:04:11 INFO populating workspace /tmp/melange-workspace-936571740 from ./test-fixtures
2024/12/13 18:04:11 INFO ImgRef = /tmp/melange-guest-3338514633
2024/12/13 18:04:11 INFO running the main test pipeline
2024/12/13 18:04:11 INFO running step "python/test"
2024/12/13 18:04:11 WARN Traceback (most recent call last): uses=python/test
2024/12/13 18:04:11 WARN   File "<string>", line 1, in <module> uses=python/test
2024/12/13 18:04:11 WARN ModuleNotFoundError: No module named 'numpy' uses=python/test
2024/12/13 18:04:11 INFO ERROR: failed to test package. the test environment has been preserved:

Not related to this PR but maybe a temporary thing with the python package?

[smoser]

minor comment inline.