Apt-cacher-ng in debian-12-minimal does't work with onion repos

[apparatus]

@apparatus

I’ll try to build apt-cacher-ng versions between 3.6.4 and 3.7.4 to find the cause of this issue and a possible proper fix to it.

The problem starts with apt-cacher-ng version 3.7-1 so it’s somewhere in 3.6 → 3.7 code.