49a9b70cb1
* Optionally enable external-helpers in tests https://github.com/babel/babel/pull/12911 was a breaking change that now requires you to keep `babel-plugin-external-helpers` in your `package.json`. It'll will probably be unnoticeable for most, because another dependency could transitively depend on it, but AMP recently hit it when cleaning up our deps. * Cast to boolean * Fix package name