See: https://github.com/nextcloud/all-in-one/discussions/6064
`pihole/pihole@latest` has been updated to `v6`,
breaking the Web Admin interface at (http://192.168.x.x:8573/admin)
(Pi-hole itself continues working fine, it seems)
**Cause:** V6 replaced `lighttpd` with an *embedded webserver*
and changed most `pi-hole.json` *environment variables*.
**Fix:** This PR updates the environment variables to match the new v6 configuration.
Stopping and starting the container will apply the changes and
should fix the Web Admin interface.
Signed-off-by: David Hund <david.hund@gmail.com>
