- Update tooling to support revised testing guide (PR #20697).
- Require jasmine upgrade for examples that use marble testing.
- Copy `cli/package.json` to `testing/` and add `jasmine-marbles`.
- Resolve merge conflicts created by `NgModules` guides.
PR Close#20165
Fixes app build error in testing guide which has testing folder at multiple levels,
with files in them referring to files in the root `testing` folder.
Also removed the exclusion of files with `.1` in the name because
all app `.ts` files must be buildable per aio policy.
must build
PR Close#20779
