Use a macro to limit error in default configuration

[sfauvel]

Content

This PR define a macro in default configuration code to use identifier instead of hard coded string. This avoids typos that are difficult to detect.

Pre-submit checklist

• Branch
  • [ ] Tests are provided (if possible)
  • [x] Crates versions are updated (if relevant)
  • [ ] CHANGELOG file is updated (if relevant)
  • [x] Commit sequence broadly makes sense
  • [x] Key commits have useful messages
• PR
  • [x] No clippy warnings in the CI
  • [x] Self-reviewed the diff
  • [x] Useful pull request description
  • [x] Reviewer requested
• Documentation
  • [ ] Update README file (if relevant)
  • [ ] Update documentation website (if relevant)
  • [ ] Add dev blog post (if relevant)

[github-actions[bot]]

Test Results

    4 files  ±0     51 suites  ±0   8m 40s :stopwatch: +6s 1 090 tests ±0  1 090 :white_check_mark: ±0  0 :zzz: ±0  0 :x: ±0  1 238 runs  ±0  1 238 :white_check_mark: ±0  0 :zzz: ±0  0 :x: ±0 

Results for commit 277c7e6f. ± Comparison against base commit de439df7.

:recycle: This comment has been updated with latest results.