migrate to eslint 9

[trixobird]

eslint 8 supports typesript up to 5.5.0. So there are warning during lint, that do not fail the build currently. In general it is a good practice to update packages to their latest version, and it is been already 4 months that eslint9 is out.

The proble for the migration is that we are dependent on @vercel/style-guide and till they migrate to the 'flat-hierarchy' or if eslint-compat introduces a tool that would do it automatically we need to wait.

I have pushed a commit that should be fine once the vercel guys make the migration. I also open two issues, one in vercel and the other in eslint-compat