Release 2.5.0

[stap-m]

Release will be done on Sept 23 or 24 by @l-emele and @stap-m to have a fresh release for the SIROP final workshop

[stap-m]

1. All issues closed and all pull requests merged that are part of the release milestone.
2. Branch releases-v1.2.3 from dev.
3. Update version information and release date in VERSION file and CITATION.cff.
4. Change unreleased heading in CHANGELOG.md.
5. Create two pull requests.
6. Automated tests are successful.
7. PR reviews.
8. Merge both PRs.
9. Close release milestone.
10. Draft release.
11. Set as the latest release.
12. Press Publish release button.
13. Create new unreleased section in CHANGELOG.md.
14. Add build files to the release page.
15. Inform @adelmemariani and @jh-RLI.

Detailled release workflow