Update jellyfin.sh / Fix infinite loop (#792)

Running the script created an infinite loop waiting for user input to confirm the installation of new packages. The -y option fixes this and allows the script to run without interaction and therefore as expected.

ct/jellyfin.sh

@@ -61,7 +61,7 @@ if [[ ! -d /usr/lib/jellyfin ]]; then msg_error "No ${APP} Installation Found!";
 msg_info "Updating ${APP} LXC"
 apt-get update &>/dev/null
 apt-get -y upgrade &>/dev/null
-apt-get --with-new-pkgs upgrade jellyfin jellyfin-server &>/dev/null
+apt-get -y --with-new-pkgs upgrade jellyfin jellyfin-server &>/dev/null
 msg_ok "Updated ${APP} LXC"
 exit
 }