Edit Script page to reflect Only supported OS

[kalikid021]

Update https://community-scripts.github.io/ProxmoxVE/scripts?id=apache-guacamole
With warning box for Supported OS versions, or amend script advanced settings to only allow supported OS'

When script runs it doesn't exit if alternate OS is chosen

Only debian 12 supported.

Originally posted by @michelroegl-brunner in #1555

[michelroegl-brunner]

You can try wich ever os you like, the defaults are printed during the advanced install in the gui. and the note that we do not support any other os then default, but others may work with ubuntu, while others do not.

The warning is clearly visible during advanced settings.