Check if Mailserver answer to VRFY and EXPN requests

The Mailserver on this host answers to VRFY and/or EXPN requests. SPDX-FileCopyrightText: 2009 Greenbone AG Some text descriptions might be excerpted from a referenced sources, and are Copyright C by the respective right holders. SPDX-License-Identifier: GPL-2.0-only ifdescription...