Start Async Challenge Content

[bonham000]

This PR:

• Start adding Async Programming Module challenges. Added sections: Timers, Async/Await, Promises/Callbacks.
• Add Promise.allSettled type definitions to the extra Monaco type definitions.
• Some edits/improvements to the test runner environment.
• Break the tests with every commit 🤷

Notes:

• Somehow, if there is a bug in the in-browser test utils which throws an error, for instance if you reference an undefined value, this error gets thrown and misses all of the catch blocks we have around the code/test execution. This results in the Workspace never canceling the loading status and getting stuck in a tests loading state. I couldn't figure out why errors like this (although they should not happen because they represent broken test code) do not get caught. 🤔
• Incidentally, the async challenges make the test loading state much more useful (previously we mentioned this might not be helpful). It's probably worth keeping.

Coming Later:

• Additional sections: Networking and HTTP, Working with APIs, Async Practice.

[iansinnott]

TIL Promise.allSettled is a thing. Nice! As an aside, what happens with Promise.all if one of them throws? Does the whole thing throw?

Break the tests with every commit 🤷

I support this 👍

Incidentally, the async challenges make the test loading state much more useful

Awesome, glad to hear

[bonham000]

@iansinnott yes, Promise.all will throw whenever any (the first) contained promise rejects, whereas Promise.allSettled will wait for all contained promises to resolve or reject and then produce an array of data representing the results. Because of this, I think Promise.allSettled should not throw errors.