Add comment flag in ssh-keygen example

Guides/install-linux.md

@@ -67,7 +67,7 @@ sudoedit /etc/ssh/sshd_config
 ### Create id to connect to servers
 
 ```sh
-ssh-keygen -f id_server_eddsa -t ed25519
+ssh-keygen -f id_server_eddsa -t ed25519 -C key-name
 ```
 
 Then add the generated public key to servers.