Upgrade to Angular 16

[arturovt]

Note: I had to move tests from workspace/tests to workspace/scroller/src/tests. This was done because Angular resolves spec files relatively different starting from 14 version.

src/builders/karma/find-tests-plugin.js has the following:

const specFiles = await findTests(include, exclude, workspaceRoot, projectSourceRoot);

Which means .spec.ts files are searched automatically relatively to projectSourceRoot, which is workspace/scroller/src.

[dhilt]

@arturovt I didn't want to pin new versions of the lib to Angular 16+ because this would be a breaking change, so I decided to extract lib/demo/tests projects keeping their own dependency lists separate. I would agree that my current approach is not the best, perhaps it can be improved in the future.

Anyway, thanks for this big contribution! If you have time, maybe you can look at my updates in your ssr PR: #342.