[Core] Allow module entrypoint to be written in typescript

[driusan]

There is an unnecessary ".js" added to the name resolution in webpack.config.js which forces the entrypoint of modules referred to by the config to be javascript. This removes it so that .ts/.tsx files can serve as the entrypoint to a module.

[driusan]

@laemtl you're probably the only one who's worked with webpack.config.js.. can you review? It's a tiny change.

[HenriRabalais]

Yeah! Looks good to me — I guess my only question is that the previous code seemed to restrict it to .js file extensions. Is the idea to remove file extension qualification entirely? Or would it be preferable to add some sort of regex check to make sure it's either .js OR .ts OR .tsx

[driusan]

I don't see why we would want to restrict the extension at all, if it's something that our webpack configuration supports.

[HenriRabalais]

lgtm