Docs: Add sponsors to each README

[nzakas]

Docs page(s)

packages/compat/README.md packages/migrate-config/README.md packages/object-schema/README.md packages/config-array/README.md

What documentation issue do you want to solve?

We aren't displaying sponsors on any of our READMEs.

What do you think is the correct solution?

Automatically update the sponsors list every day like we do in eslint/eslint.

Participation

• [ ] I am willing to submit a pull request for this change.

Additional comments

No response

[harish-sethuraman]

I'll pick this.

To confirm:

• we would need to add https://github.com/eslint/eslint/blob/main/tools/update-readme.js similar to main repo and update readme of all packages and the repo's readme itself?

[nzakas]

That's correct.