build: fix test-based Stackblitz examples

Fixes an error when running the harness examples in Stackblitz.

Author: alan-agius4

docs/src/app/shared/stackblitz/stackblitz-writer.ts

@@ -40,7 +40,6 @@ const TEMPLATE_PATH = '/assets/stackblitz/';
  */
 export const TEMPLATE_FILES = [
   'angular.json',
-  'karma.conf.js',
   'package.json',
   'package-lock.json',
   'tsconfig.app.json',
@@ -49,7 +48,6 @@ export const TEMPLATE_FILES = [
   'src/index.html',
   'src/main.ts',
   'src/styles.css',
-  'src/test.ts',
 ];
 
 /**

docs/src/assets/stackblitz/angular.json

@@ -79,10 +79,8 @@
         "test": {
           "builder": "@angular/build:karma",
           "options": {
-            "main": "src/test.ts",
             "polyfills": ["zone.js", "zone.js/testing"],
             "tsConfig": "tsconfig.spec.json",
-            "karmaConfig": "karma.conf.js",
             "inlineStyleLanguage": "css",
             "assets": ["src/assets"],
             "styles": ["src/styles.css", "@angular/material/prebuilt-themes/azure-blue.css"],