fix: validate edge_functions in config

[jackiewmacharia]

Summary

Fixes https://github.com/netlify/pillar-runtime/issues/238

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[eduardoboucas]

Looking good! I think we'll also want to validate the objects inside edge_functions. Also, we'll need some tests.

[eduardoboucas]

Also, we shouldn't be using the chore: prefix for changes in runtime functionality. This should be a feat: or a fix:, otherwise release-please won't generate a release from it.

[jackiewmacharia]

@eduardoboucas this one is now ready.

[eduardoboucas]

Awesome work! 🎉