🐞 Bug report

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Is this a regression?

Description

🔬 Minimal Reproduction

ng g guard auth/test --implements CanLoad

🔥 Exception or Error

🌍 Your Environment

@angular-devkit/architect         0.1000.8
@angular-devkit/build-angular     0.1000.8
@angular-devkit/build-optimizer   0.1000.8
@angular-devkit/build-webpack     0.1000.8
@angular-devkit/core              10.0.8
@angular-devkit/schematics        10.0.8
@angular/cdk                      10.2.0
@angular/cli                      10.0.8
@angular/material                 10.2.0
@ngtools/webpack                  10.0.8
@schematics/angular               10.0.8
@schematics/update                0.1000.8
rxjs                              6.5.5
typescript                        3.9.7
webpack                           4.43.0

Anything else relevant?

The generated class:

export class TestGuard implements CanLoad {
  canLoad(
    route: Route,
    segments: UrlSegment[]): Observable<boolean> | Promise<boolean> | boolean {
    return true;
  }
}

Should be:

export class TestGuard implements CanLoad {
  canLoad(
    route: Route,
    segments: UrlSegment[]): Observable<boolean | UrlTree> | Promise<boolean | UrlTree> | boolean | UrlTree {
    return true;
  }

}

The return type is not correct, according to angular docs | UrlTree is missing