Comment 0 for bug 1877454

Please consider applying this change to openssh-server distributed in Xenial (16.04).
Without it, sshd can sporadically hang when making use of the `AuthorizedKeysCommand` option.

https://github.com/openssh/openssh-portable/commit/ddd3d34e5c7979ca6f4a3a98a7d219a4ed3d98c2