Fix pending test: integration test for run_with_timer_and_beep.

It took us forever to realize that stdout couldn't be read from rspec because:
1) We were forced to override our local definition of "output" to get at Rspec's
2) We got a clever workaround for that
3) The workaround helped for unit test, but not integration test, because run_with_timer_and_beep was running in a subprocess (and not rspec's process).

If we hadn't overridden "output", this rabbit hole would never have invited us.