"Sign your PR" reminder is missing in CONTRIBUTING.md

[lenicatko]

Contributing.md doesn't mention sign-off. I realized that only after creating PR, that I am missing my signature. Adding it there would be very helpful for a new contributor.

Adding the same section as it is in this repository could fix it: https://github.com/cri-o/cri-o/blob/main/CONTRIBUTING.md#sign-your-prs

[haircommander]

good find!

[haircommander]

do you have interest in submitting a PR to fix (or include it in #58) or would you like me to?

[lenicatko]

@haircommander Sure, I can do that, I just wanted to ask if you want me to just add the link to the other repository or it is better to paste the entire section text here as well?

[haircommander]

I find myself thinking about maintenance overhead. Maybe adding a line For additional tips on contribution, check out the upstream documentation with a link to it? Then we only have to edit in one place

[lenicatko]

@haircommander good thinking! Let me add a commit to my opened PR.