refactor(@schematics/angular): inject the service at setup

Author: kasaharu

packages/schematics/angular/service/files/__name@dasherize@if-flat__/__name@dasherize__.service.spec.ts.template

@@ -3,10 +3,14 @@ import { TestBed } from '@angular/core/testing';
 import { <%= classify(name) %>Service } from './<%= dasherize(name) %>.service';
 
 describe('<%= classify(name) %>Service', () => {
-  beforeEach(() => TestBed.configureTestingModule({}));
+  let service: <%= classify(name) %>Service;
+
+  beforeEach(() => {
+    TestBed.configureTestingModule({});
+    service = TestBed.get(<%= classify(name) %>Service);
+  });
 
   it('should be created', () => {
-    const service: <%= classify(name) %>Service = TestBed.get(<%= classify(name) %>Service);
     expect(service).toBeTruthy();
   });
 });