test: fix failing test by adding zone.js in angular setup

Author: wnvko

packages/igx-templates/igx-ts-legacy/projects/_base/files/angular.json

@@ -94,7 +94,10 @@
         "test": {
           "builder": "@angular-devkit/build-angular:karma",
           "options": {
-            "polyfills": "src/polyfills.ts",
+            "polyfills": [
+              "zone.js",
+              "zone.js/testing"
+            ],
             "tsConfig": "tsconfig.spec.json",
             "inlineStyleLanguage": "scss",
             "styles": [