Wrong handling of 'undocumented' attributes with jsdoc 3.6.x

[alxroyer]

As noticed by jsdoc#1672, jsdoc 3.6.x output differs from 3.5.x, especially on undocumented attributes strangely set to true while the comment attribute is correctly set with some user comment.

The effect for tsd-jsdoc is that such doclets are not managed anymore.

Steps to reproduce :

• checkout tsd-jsdoc, run npm install but then force the installation of jsdoc with version 3.6.3.
• npm run build
• npm run test => failure

[englercj]

Yeah there are a bunch of backwards incompatible changes to jsdoc 3.6. I really wish they had done a major release.

I think in this lib we need to update to work with 3.6, and change how we determine exports (a la #100), then do a major release on our side.

[alxroyer]

I've just committed a sample of code to fix this problem.
See changes on publish.ts in PR#98.