When update ISPConfig, if a custom port is setted for apps domain it returns to the default 8081, only on the config file (remains custom on the web panel)
## short description
When updating ISPConfig if App Domain have a non standard value it come back on the default 8081 even if the Web Panel reports the custom port.
## correct behaviour
App domain should remain on the custom port as setted on the web panel.
## environment
Server OS: Ubuntu
Server OS version: 20.04.01
ISPConfig version: <= 3.2.1
issue