fix(@schematics/angular): reformat app.config.ts

The CLI usually generates files with a new line at the end.
This line was lacking in the new `app.config.ts` file generated for standalone applications.

It was also using a trailing comma, which is not the usual convention in generated files.

Author: cexbrayat

packages/schematics/angular/application/files/standalone-files/src/app/app.config.ts.template

@@ -4,5 +4,5 @@ import { provideRouter } from '@angular/router';
 import { routes } from './app.routes';<% } %>
 
 export const appConfig: ApplicationConfig = {
-  providers: [<% if (routing) { %>provideRouter(routes) <% } %>],
-};
+  providers: [<% if (routing) { %>provideRouter(routes) <% } %>]
+};