Database remote ip config cannot be changed

short description

Changing the remote ip access in the database configuration throws the error: "At least one of the entered ip addresses is invalid."

The textbox content is also updated adding a trailing comma to the list of ips. The new config cannot be saved.

correct behaviour

Saving without error where there is a valid ips list.

environment

Multiserver installation. db , web and ispconfig panel frontend are managed by different servers.