Fix fallthrough when git-lfs-authenticate returns an error
Fix fallthrough when git-lfs-authenticate returns an error

If using an SSH URL and git-lfs-authenticate returns an error, without
this change the error is just reported to the trace but execution
continues.

A common result is a completely made up LFS URL being returned which
then 404's, which ends up setting lfs.batch=false. If the server doesn't
implement the non-batch interface, this config then breaks LFS even
after the SSH issue is resolved & has to be manually removed.

Jericho25/-git-lfs_miilkyway,github/git-lfs,ryansimmen/git-lfs,dakotahawkins/git-lfs,github/git-lfs,github/git-lfs,larsxschneider/git-lfs,aleb/git-lfs,andyneff/git-lfs,ryansimmen/git-lfs,dakotahawkins/git-lfs,larsxschneider/git-lfs,larsxschneider/git-lfs,dakotahawkins/git-lfs,ttaylorr/git-lfs,andyneff/git-lfs,bozaro/git-lfs,aleb/git-lfs,andyneff/git-lfs,aleb/git-lfs,ryansimmen/git-lfs,bozaro/git-lfs,ttaylorr/git-lfs,Jericho25/-git-lfs_miilkyway,ttaylorr/git-lfs,Jericho25/-git-lfs_miilkyway,bozaro/git-lfs