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
1d378e2987