KBU appears to have IPv6 Issues

[AiyionPrime]

nslookup map.kbu.freifunk.net

yields

Server:		10.18.0.1
Address:	10.18.0.1#53

Non-authoritative answer:
map.kbu.freifunk.net	canonical name = bonn7.kbu.freifunk.net.
Name:	bonn7.kbu.freifunk.net
Address: 157.90.178.15
Name:	bonn7.kbu.freifunk.net
Address: 2a01:4f8:252:2db0::2

but the server does not really respond via IPv6.
This leads to an avoidable wait of 5s until requests performs a fallback to IPv4.

curl -6 https://map.kbu.freifunk.net/data/ffkbub-V2/meshviewer.json

@ff-kbu might one of you look into this?