[arch-general] Dangerous dbus update for testing

There's a dangerous dbus update coming up for the testing repository. The package itself isn't so special, as it works fine, but the fact that every dbus-daemon process on your system will crash during the upgrade can lead to unpleasant surprises. Testing users: please be aware of this and run your upcoming upgrades from a plain text console instead of from X. One of the unpleasant surprises is that xorg-server in testing goes down with dbus while it's upgrading, leading to loss of important work or an interrupted package upgrade process.