Notable changes for 4.1

[orta]

Changes which could affect builds:

• https://github.com/microsoft/TSJS-lib-generator/pull/873 Updates the specs -> .d.ts for the DOM .d.ts file to take into account more ways to declare something should not exist. Removing some types which aren't declared to be inside the JS runtime anymore.

• https://github.com/microsoft/TSJS-lib-generator/pull/877 Adds webworker.iterable.generated.d.ts (which will need some compiler work to have it show up correctly)

• https://github.com/microsoft/TSJS-lib-generator/pull/879 Removes HkdfCtrParams from the Web Cryptography API which was deprecated in 2016, replaced with HkdfParams which is in the current spec.

• https://github.com/microsoft/TSJS-lib-generator/pull/883 Switches the global variable name from never to void which means you will get an error if you read it. This was nearly always a mistake, we used to raise if you write to it, now you get it if you write.