Add .errors to the @babel/parser return type definitions

[sosukesuzuki]

Q	A
Fixed Issues?	N/A
Patch: Bug Fix?	Y
Tests Added + Pass?	Yes
License	MIT

This PR fixes it on the babel-parser side, or should fix it on the babel-types side?

[babel-bot]

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[nicolo-ribaudo]

This PR fixes it on the babel-parser side, or should fix it on the babel-types side?

It's correct like this: they technically aren't part of the AST, but @babel/parser attatches them as an extra property.