Fix netlify doc links

[omnibs]

Netlify deprecated automatic redirects of netlify.com (meant to host netlify-the-company content) to netlify.app (meant ot host netlify customer content). See: https://answers.netlify.com/t/deprecating-automatic-com-redirects/115442

The documentation links to netlify are now all broken :<

In this PR I just replaced netlify.com for netlify.app in this codebase.

• [ ] ran tests locally with npm test <- didn't run bc just .md files
• [x] updated CHANGELOG.md if appropriate <- retroactively updated all netlify links there

ps: I didn't think this merited a new CHANGELOG entry, but lmk if you think it does!

[omnibs]

These failing netlify steps are not in CI.yml in the repo, right?

I tried pushing changes to it, but it doesn't seem to affect them.

[avh4]

Hmm, I tried to take a quick look, but I don't see where to figure out how netlify is configuring its environment.

I guess I'll try to move this to static webhosting to avoid letting netlify product changes break everything again.

[HadrienMP]

Hey ! I noticed the problem is still present, will this PR be merged ?