Fix KPN ipv6 with UDM (pro)

KPN IPV6 with UDM (pro).md

Steps

1. Get into the unifios shell on your udm

   unifi-os shell

2. Download udm-boot_1.0.5_all.deb and install it and go back to the UDM. The latest package will always be found at https://udm-boot.boostchicken.dev

   curl -L https://udm-boot.boostchicken.dev -o udm-boot_*_all.deb
   dpkg -i udm-boot_*_all.deb
   exit

3. install the ipv6 fix for KPN:

   cd /mnt/data/on_boot.d/10-fix_ipv6.sh
   curl -L https://udm-boot.boostchicken.dev -o udm-boot_*_all.deb
   dpkg -i udm-boot_*_all.deb
   exit

(source: https://github.com/boostchicken/udm-utilities/tree/master/on-boot-script#steps)