Add support for Debian bookworm

Issue/feature addressed

No CI or packaging support for the current Debian stable release was present.

Proposed solution

Add new CI jobs to test on Debian bookworm and fix issues which arose from compiling on this distribution.

Implementation

• New jobs were added to the CI and packaging pipelines.
• Documentation now built using bookworm, instead of bullseye.
• Fix compiler error in HTML version of user guide.
• Temporarily disable parallel movement test which fails.
• Updates the VERSION to 5.4.0.

Tests

Suggested reviewers

@dmoxey

Notes

Most of the Debian/bookworm files are just a copy of the bullseye files.

Checklist

• Functions and classes, or changes to them, are documented.
• User guide/documentation is updated.
• Changelog is updated.
• Suitable tests added for new functionality.
• Contributed code is correctly formatted. (See the contributing guidelines).
• License added to any new files.
• No extraneous files have been added (e.g. compiler output or test data files).