Revert "fix(angular): replace Custom Angular Builder with Standard Angular CLI Builder (#50)" (#52)

This reverts commit 6d56092.

Reason: broken angular.json configuration

Author: alxhub

angular/angular.json

@@ -8,7 +8,7 @@
     "demo": {
       "architect": {
         "build": {
-          "builder": "@angular-devkit/build-angular:application",
+          "builder": "@angular/build:application",
           "configurations": {
             "development": {
               "extractLicenses": false,
@@ -37,7 +37,7 @@
           }
         },
         "serve": {
-          "builder": "@@angular-devkit/build-angular:dev-server",
+          "builder": "@angular/build:dev-server",
           "configurations": {
             "development": {
               "buildTarget": "demo:build:development"