Use the `-q` (quiet) option to ssh and scp, to suppress the `/etc/motd` (and related) messages.
While `Banner` might seem to be related, it is not. Refer to `sshd_config` manual:
> The contents of the specified file are sent to the remote user before authentication is allowed. If the argument is none then no banner is displayed. **By default, no banner is displayed**.
You could use `PrintMotd` (in `sshd_config`):
> **`PrintMotd`**
> Specifies whether sshd(8) should print `/etc/motd` when a user logs in interactively. (On some systems it is also printed by the shell, `/etc/profile`, or equivalent.) The default is yes.
but in scripting, I simply use the `-q` option (requiring less configuration of the server).