init-launch-sandbox: Stop capturing stdout/stderr

[auscompgeek]

This stops capturing and buffering stdout and stderr when installing extensions in the sandbox, so live progress is visible.

Checklist

• [ ] I have added tests

[AndreasArvidsson]

Yes there was problem with the output on windows. I can try this on when I get back home

[auscompgeek]

Hmm. I ran this on macOS, haven't tried on other platforms. If it's a problem I guess we can keep piping and reprint the stream?

[pokey]

@AndreasArvidsson when you get a minute it would be awesome if you could try this out on Windows; I believe that's what's blocking this PR

[AndreasArvidsson]

stdout appears to be working on windows

[pokey]

@AndreasArvidsson do you remember what the problem was originally? Unfortunately we didn't leave any comment. Here's the commit where you fixed Windows originally fwiw

[AndreasArvidsson]

I think it was that stdout wasn't showing. I can't remember exactly. Now it appears to be working at least.