Update panel.md

change node version to 20 as 16 is decrepted

Author: ayu2606

community/customization/panel.md

@@ -17,11 +17,11 @@ The build tools require NodeJS, yarn is used as the package manager.
 
 ```bash
 # Ubuntu/Debian
-curl -sL https://deb.nodesource.com/setup_16.x | sudo -E bash -
+curl -sL https://deb.nodesource.com/setup_20.x | sudo -E bash - 
 sudo apt install -y nodejs
 
 # CentOS
-curl -sL https://rpm.nodesource.com/setup_16.x | sudo -E bash -
+curl -sL https://rpm.nodesource.com/setup_20.x | sudo -E bash -
 sudo yum install -y nodejs yarn # CentOS 7
 sudo dnf install -y nodejs yarn # CentOS 8, Rocky Linux 8, AlmaLinux 8
 ```