chore: upgrade to Angular 11

[arturovt]

I've upgraded Angular to the latest version to ensure that nothing is broken.

I've also disabled Ivy when library is built, since it's not recommended:

If you are a library author, you should keep using the View Engine compiler as of version 9. By having all libraries continue to use View Engine, you will maintain compatibility with default v9 applications that use Ivy, as well as with applications that have opted to continue using View Engine.

P.S. we're using the View Engine in serving mode, since the app is huge and it's much faster.