outdated: allow passing formulae as arguments.

If formulae names are passed as arguments check if just they are outdated. Additionally, return a failed code if they are outdated.

This will hopefully be able to stop people complaining about the outdated error code as they can now just run e.g.:
`brew outdated git && brew upgrade git`

Closes #31242.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>