Build dies when trying to remove ephemeral keys

==> amazon-ebs: Trying to remove ephemeral keys from authorized_keys files

==> amazon-ebs: sed: can’t read /root/.ssh/authorized_keys: No such file or directory

==> amazon-ebs: rm: cannot remove ‘/root/.ssh/authorized_keys.bak’: No such file or directory

==> amazon-ebs: Stopping the source instance…