angular update to version 12

first step: ng update @angular/core@12 @angular/cli@12

pdb-js/src/environments/environment.ts

@@ -13,4 +13,4 @@ export const environment = {
  * This import should be commented out in production mode because it will have a negative impact
  * on performance if an error is thrown.
  */
-// import 'zone.js/dist/zone-error';  // Included with Angular CLI.
+// import 'zone.js/plugins/zone-error';  // Included with Angular CLI.

pdb-js/src/polyfills.ts

@@ -55,7 +55,7 @@
 /***************************************************************************************************
  * Zone JS is required by default for Angular itself.
  */
-import 'zone.js/dist/zone';  // Included with Angular CLI.
+import 'zone.js';  // Included with Angular CLI.
 
 
 /***************************************************************************************************

pdb-js/src/test.ts

@@ -1,6 +1,6 @@
 // This file is required by karma.conf.js and loads recursively all the .spec and framework files
 
-import 'zone.js/dist/zone-testing';
+import 'zone.js/testing';
 import { getTestBed } from '@angular/core/testing';
 import {
   BrowserDynamicTestingModule,