👷📝 build RtD on Ubuntu 24.04 (#555)

## Description

This pull request updates the documentation build process to Ubuntu
24.04 on ReadTheDocs.

## Checklist:

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- [x] The pull request only contains commits that are related to it.
- [x] I have added appropriate tests and documentation.
- [x] I have made sure that all CI jobs on GitHub pass.
- [x] The pull request introduces no new warnings and follows the
project's style guidelines

Signed-off-by: burgholzer <burgholzer@me.com>

.readthedocs.yaml

@@ -5,7 +5,7 @@ formats:
   - htmlzip
 
 build:
-  os: ubuntu-22.04
+  os: ubuntu-24.04
   tools:
     python: "3.12"
   commands: