fix(ivy): restore `fixmeIvy` imports for Router-related tests (#27720)

It looks like `fixmeIvy` imports were accidentally removed from Router integration tests, thus causing build errors. The necessary imports are now restored and the project should build normally.

PR Close #27720

packages/router/test/BUILD.bazel

@@ -12,6 +12,7 @@ ts_library(
         "//packages/platform-browser",
         "//packages/platform-browser-dynamic",
         "//packages/platform-browser/testing",
+        "//packages/private/testing",
         "//packages/router",
         "//packages/router/testing",
         "@rxjs",

packages/router/test/integration.spec.ts

@@ -12,6 +12,7 @@ import {ChangeDetectionStrategy, Component, Injectable, NgModule, NgModuleFactor
 import {ComponentFixture, TestBed, fakeAsync, inject, tick} from '@angular/core/testing';
 import {By} from '@angular/platform-browser/src/dom/debug/by';
 import {expect} from '@angular/platform-browser/testing/src/matchers';
+import {fixmeIvy} from '@angular/private/testing';
 import {ActivatedRoute, ActivatedRouteSnapshot, ActivationEnd, ActivationStart, CanActivate, CanDeactivate, ChildActivationEnd, ChildActivationStart, DetachedRouteHandle, Event, GuardsCheckEnd, GuardsCheckStart, Navigation, NavigationCancel, NavigationEnd, NavigationError, NavigationStart, PRIMARY_OUTLET, ParamMap, Params, PreloadAllModules, PreloadingStrategy, Resolve, ResolveEnd, ResolveStart, RouteConfigLoadEnd, RouteConfigLoadStart, RouteReuseStrategy, Router, RouterEvent, RouterModule, RouterPreloader, RouterStateSnapshot, RoutesRecognized, RunGuardsAndResolvers, UrlHandlingStrategy, UrlSegmentGroup, UrlSerializer, UrlTree} from '@angular/router';
 import {Observable, Observer, Subscription, of } from 'rxjs';
 import {filter, first, map, tap} from 'rxjs/operators';