Changes:
- Change the project type to `service-worker`, so that it gets
appropriate `package.json` (with `@angular/service-worker` dependency)
and `angular.json` (with `serviceWorker: true` in production config).
- Move `ngsw-config.json` to the correct directory.
- Specify custom test commands for aio's `yarn example-e2e` to also
verify that the ServiceWorker bits are set up correctly.
PR Close#28020
Since `versionedFiles` behaves in the exact same way as `files`, there
is no reaason to have both. Users should use `files` instead.
This commit deprecates the property and prints a warning when coming
across an asset-group that uses it. It should be completely removed in
a future version.
Note, it has also been removed from the default `ngsw-config.json`
template in angular/devkit#754.
PR Close#23584