Breaks output typescript types

[ChuckJonas]

When using this package, we are getting an odd typescript error after transpilation. tsc completes successfully, but the "output" .d.ts files this error:

Namespace "yup" has no exported member 'default' in output

I believe this might have something to do with this package importing an old version of "@types/yup": "^0.29.13",. It seems like the most recent version of yup is actually written in typescript (or at least provides it's own types), so this shouldn't be necessary.