Microfrontend support

# 🚀 Feature request
Webpack 5 Module Federation API will be a game changer to the web.
So bringing support to Angular CLI once Webpack 5 is released and supported will also be a game changer to Angular projects using the CLI.

### Command (mark with an `x`)

- [ ] new
- [ ] build
- [ ] serve
- [ ] test
- [ ] e2e
- [ ] generate
- [ ] add
- [ ] update
- [ ] lint
- [ ] xi18n
- [ ] run
- [ ] config
- [ ] help
- [ ] version
- [ ] doc

### Description
Once Angular CLI support Webpack 5 #17555 it is important to also support its new API called Module Federation that allow sharing modules in runtime among applications.

### Describe the solution you'd like
Support Webpack 5 Module Federation.

### Describe alternatives you've considered
No alternative considered.

Start by reading Angular CLI issue #17555 and the CLI's build and serve entry points, then review the Webpack 5 Module Federation API requirements. Done means defining and implementing Angular CLI support for sharing modules at runtime among applications, with the relevant CLI behavior covered by tests.

Scritto dal modello di indicizzazione a partire dal testo della issue.