Live config may be fetched from wrong repository

[colans]

On the destination, there is a git fetch command to grab configuration from the source. However, no repository is specified. As per the man page (emphasis mine),

When no remote is specified, by default the origin remote will be used, unless there’s an upstream branch configured for the current branch.

This is different than this Drush command, which always defaults to origin:

--remote= The remote git repository to use to fetch changes. Defaults to "origin".

The upstream branch can often be the developer's fork (named after the developer, let's say), not origin (or what I prefer to call upstream to avoid ambiguity).

So we should specify the remote repository here. I'll have a patch for this shortly.