Change .desktop file icon to utilities-system-monitor.  Closes: #6701.
Change .desktop file icon to utilities-system-monitor.  Closes: #6701.

tonypaulic/xfce4-genmon-plugin,tonypaulic/xfce4-genmon-plugin,xfce-mirror/xfce4-genmon-plugin,xfce-mirror/xfce4-genmon-plugin,tonypaulic/xfce4-genmon-plugin,dnschneid/xfce4-genmon-plugin,dnschneid/xfce4-genmon-plugin,dnschneid/xfce4-genmon-plugin,xfce-mirror/xfce4-genmon-plugin