Update nginxproxymanager.sh

Maintain compatibility with older versions of Node.js
fixes https://github.com/tteck/Proxmox/issues/2733

ct/nginxproxymanager.sh

@@ -61,6 +61,7 @@ function update_script() {
   fi
   if ! command -v pnpm &> /dev/null; then  
     msg_info "Installing pnpm"
+    export NODE_OPTIONS=--openssl-legacy-provider
     npm install -g pnpm@8.15 &>/dev/null
     msg_ok "Installed pnpm"
   fi