Add CI static checks for built-in documentation

[limbonaut]

This will help verify whether we cover the API changes in documentation.

[bruno-garcia]

this can prob be added with danger.js

[limbonaut]

We'll need to build it first before we can verify it. The idea is to create a build, regenerate documentation with the built library, and check if there are any changes in the working tree. If so, it means, that the API changed, but the built-in docs were not updated to reflect those changes.