* CI: Add Debian 13 Trixie (#1113)
* Add Debian 13 Trixie to CI.
* I don't think this is needed any longer.
* Debian: adjust way GPG signature is installed for Docker's software repo.
(cherry picked from commit 1ba34b9b7c)
* Skip Docker Compose v1 on Debian Trixie.
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Co-authored-by: Felix Fontein <felix@fontein.de>
