fix(module:schematics): import RouterLink (#8621)

Every time 'side-menu' is chosen when adding ng-zorro-antd into Angular project, app.component.html uses RouterLink in Dashboard/welcome router, but the Routerlink is not imported in app.component.ts

Author: JavaProgrammerLB

schematics/ng-generate/side-menu/standalone/src/app/app.component.ts.template

@@ -1,14 +1,14 @@
 import { Component } from '@angular/core';
 import { CommonModule } from '@angular/common';
-import { RouterOutlet } from '@angular/router';
+import { RouterLink, RouterOutlet } from '@angular/router';
 import { NzIconModule } from 'ng-zorro-antd/icon';
 import { NzLayoutModule } from 'ng-zorro-antd/layout';
 import { NzMenuModule } from 'ng-zorro-antd/menu';
 
 @Component({
   selector: '<%= prefix %>-root',
   standalone: true,
-  imports: [CommonModule, RouterOutlet, NzIconModule, NzLayoutModule, NzMenuModule],
+  imports: [CommonModule, RouterLink, RouterOutlet, NzIconModule, NzLayoutModule, NzMenuModule],
   templateUrl: './app.component.html',
   styleUrls: ['./app.component.<%= style %>']
 })