test(language-service): Remove unused code in test project (#37122)

This commit removes the `bootstrap()` function in the test project since
its presence has no effect on the behavior of language service.

Also removes the explicit cast when instantiating `CounterDirectiveContext`,
and let type inference takes care of that.

PR Close #37122

packages/language-service/test/project/app/main.ts

@@ -27,7 +27,3 @@ import * as ParsingCases from './parsing-cases';
 })
 export class AppModule {
 }
-
-declare function bootstrap(v: any): void;
-
-bootstrap(AppComponent);

packages/language-service/test/project/app/parsing-cases.ts

@@ -49,7 +49,7 @@ export class CounterDirective implements OnChanges {
   ngOnChanges(_changes: SimpleChanges) {
     this.container.clear();
     for (let i = 0; i < this.counter; ++i) {
-      this.container.createEmbeddedView(this.template, new CounterDirectiveContext<number>(i + 1));
+      this.container.createEmbeddedView(this.template, new CounterDirectiveContext(i + 1));
     }
   }
 }