This commit updates the docs examples to Angular v10.1.3. In addition to
updating the dependencies versions, it also updates the project's
structure and config to more closely match what a new v10 CLI app would
look like. See, also, the [diff][1] between a basic v9.1.4 CLI app and a
v10.1.3 one.
[1]: https://github.com/cexbrayat/angular-cli-diff/compare/9.1.4..10.1.3
PR Close#38993
Update `tsconfig[.*].json`.
Also, all make necessary changes to ensure the example apps can be
successfully built with the new, stricter type-checking options.
PR Close#36015
- Update the `stackblitz.json` config files (used for generating
Stackblitz projects and ZIP archives) to include the correct files
(taking into account the current layout of the example projects).
- Update the boilerplate files for `testing` examples to match the
current layout of the example projects.
PR Close#31937
