apt repository: Fix Origin, Label and Suite metadata

[dom6770]

The repository at http://deb.gierens.de right now has weird, unconventional metadata values:

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Hash: SHA256

Origin: . stable
Label: . stable
Suite: stable
Codename: stable
Date: Sun, 12 Oct 2025 20:56:02 UTC
Architectures: amd64 arm64 armhf
Components: main
Description: Generated by aptly

It would be helpful to update the metadata to better values, maybe something like this:

Origin: deb.gierens.de
Label: eza
Suite: stable

I discovered this during unattended-upgrades setup, and wanted to include eza, but with the current values right now, it's not clear what I would update. Just adding "o=. stable"; would definitely confuse me later.

Pinging @gierens 🙂