fix: use version name instead of testing

[p00rt]

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Description

when trying to build from the debian base image, you get a dependency conflict and are unable to build because the image is based on bookworm but the Dockerfile adds testing repositories which are currently trixie not bookworm. This change makes sure we only use bookworm at all times.

Type of change

• Bug fix (non-breaking change which fixes an issue)

Checklist

• My code follows the style guidelines of this project
• I ran ESLint and other linters for modified files
• I have performed a self-review of my own code and tested it
• I have commented my code, particularly in hard-to-understand areas (including JSDoc for methods)
• My changes generates no new warnings
• My code needed automated testing. I have added them (this is optional task)

[CommanderStorm]

Problem with the proposed change is that this debumps apprise a lot...

See https://tracker.debian.org/pkg/apprise:

• stable: 1.2.0-1
• testing: 1.8.0-2

v1.2.0 was back in November 2022..

[louislam]

Omg, is there any "lock mechanism" like npm's package-lock.json in apt?