fix: make dependabot commit message follow conventional commits

[dlaehnemann]

for conventional commits, see:
https://www.conventionalcommits.org/en/v1.0.0/

for a good cheat sheet, see:
https://kapeli.com/cheat_sheets/Conventional_Commits.docset/Contents/Resources/Documents/index

[dlaehnemann]

Also, I filed an issue with the current CI Coverage step failure, as the error message requested this (and suggested this is some compiler-internal bug).

[dcroote]

Release Please considers deps a 'releasable unit', but not chore (docs). I think it'd therefore be nicer to prefix with deps so that Release Please includes dependency updates in the release / changelog, like here for example. What do you think?

[dlaehnemann]

Yes, that makes perfect sense. I just looked for what matched our case closest in the conventional commits cheat sheet, but didn't check on release please. Many thanks for this suggestion, I'll amend both PRs accordingly.

[dlaehnemann]

Feel free to merge both, once the tests pass. I think it is currently OK to ignore the Coverage step failure, as this seems to be a nightly compiler bug.

[dcroote]

Thanks for the update and your code comment will definitely be helpful for anyone curious about the prefix.