text-only output: log stdout/stderr of steps
Created by: mrnugget
This is part of https://github.com/sourcegraph/sourcegraph/issues/23496 and adds the logging of STDOUT/STDERR of steps to the -text-only
output. Please see the comment I left for more info on how the interface could be improved/extended.
Also: turns out I don't need the process.Logger
that was extracted in https://github.com/sourcegraph/sourcegraph/pull/24545 and instead what's needed is the IntervalLogger
here that flushes the captured output with a delay (so we don't create a new huge JSON message for every line)