[AngularFireAuthGuard] Expose ways to call canActivateChild on the guard or in the route definition

[Jak3b0]

Version info

Angular: 9.0.0-next.8

Firebase: 6.6.1

AngularFire: 5.2.1

Other (e.g. Ionic/Cordova, Node, browser, operating system):

Expected behavior

I need to be able to tell the guard to also check for child routes. This could be done via some sort of option I can pass to the guard or via using a canActivateChild exported by @angular/fire/auth-guard (like the canActivate one)

[debuggerpk]

is it okay if i submit a PR for this?

[playgamemy]

Is this function going to be added? I need that to be able to use that for canActivateChild method, but at the moment somehow it returns an error but not if I pass the guard to canActivate