Tests print too much to stdout/stderr

[srawlins]

Currently pub run test prints > 2400 lines to stdout/stderr. This makes it hard to follow when one test case fails, as the stack trace can scroll up pretty far.

There are a few places which can reduce this count, something like Package.warn, the print function on the zone, etc. The integration tests may be harder.

I'd say the acceptance criteria can be something like < 500 lines.

[srawlins]

This has been reduced to ~1400 lines 🎉 . Still noisy.

[srawlins]

I got this down to 217 lines of output via test_process. 🎉

Of course 0 is better, but I'm closing this as mission accomplished.