fr(Google-maps): Add option to draw directions

#### Feature Description
Hi,
Please add option to define api key during import `GoogleMapsModule` like in `@agm/core` package.
It would be nice to be able to draw directions.

Loading google maps in head blocks frontend on 1500ms
#### Use Case
Without that features I'm not able to:
- use proper api key when I have 3 environments
- draw directions

Start by locating GoogleMapsModule and comparing its import options with the @agm/core package. Review how Google Maps is loaded and how directions could be drawn; done means supporting an environment-specific API key and directions without blocking the frontend during initial loading.

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