Update cockpit-install.sh

use backports

install/cockpit-install.sh

@@ -22,7 +22,10 @@ $STD apt-get install -y mc
 msg_ok "Installed Dependencies"
 
 msg_info "Installing Cockpit"
-$STD apt install -y cockpit --no-install-recommends
+source /etc/os-release
+echo "deb http://deb.debian.org/debian ${VERSION_CODENAME}-backports main" >/etc/apt/sources.list.d/backports.list
+$STD apt-get update
+$STD apt-get install -t ${VERSION_CODENAME}-backports cockpit -y
 sed -i "s/root//g" /etc/cockpit/disallowed-users
 msg_ok "Installed Cockpit"