SshCommand: Only force username when requested

[ChlodAlejandro]

This removes the use of the result of whoami in determining the SSH user to run the command as. This means a provided username will be respected, follow by an ~/.ssh/config-defined User, in that order.

This fixes SshCommand ignoring the config-defined User and prevents the use of whoami on Windows, which would return a machine\user format instead of just user (the default when no explicit username is provided when running the built-in OpenSSH client).

[ChlodAlejandro]

@MusikAnimal SshCommand was originally introduced in 3b0a99d with the whois step already included. Would removing the extra whois step be okay? I don't see anything in the commit message or Phabricator task that would imply something breaking here, but I wanted to ask out of an abundance of caution.

[MusikAnimal]

@MusikAnimal SshCommand was originally introduced in 3b0a99d with the whois step already included. Would removing the extra whois step be okay? I don't see anything in the commit message or Phabricator task that would imply something breaking here, but I wanted to ask out of an abundance of caution.

@ChlodAlejandro To be honest, I don't remember adding the whoami code seen on L48-50, lol. If it needs to be rewritten or something, go for it, so long as the command works without Docker too and without specifying a username (we want to make connecting as simple as possible).

[ChlodAlejandro]

This should be fine as-is then. Thanks! PR is ready for reviews.

[MusikAnimal]

Works great in my testing! Merging

[samwilson]

Release tagged.