feat(vhserver): add hint to valheim password length (#3216)

* Add hint to valheim password length

Add hint to default config file. If password is shorten than 5 characters the server did not start.

lgsm/config-default/config-lgsm/vhserver/_default.cfg

@@ -10,6 +10,7 @@
 
 ## Predefined Parameters | https://docs.linuxgsm.com/configuration/start-parameters
 servername="Valheim Server"
+# Minimum password length is 5.
 serverpassword=""
 port="2456"
 gameworld="${selfname}"