message: ci: update demo libs build options
  Listen on a different port than the main app. Now will listen on port 4201.
  Remove unit test configuration for demo libs, no unit test required for it.
diff: "serve": {
  "builder": "@angular-devkit/build-angular:dev-server",
  "options": {
  - "browserTarget": "demo-libs:build"
  + "browserTarget": "demo-libs:build",
  + "port": 4201
  },
  "configurations": {
  "production": {
  ],
  "exclude": ["**/node_modules/**"]
  }
  - },
  - "test": {
  - "builder": "@angular-devkit/build-angular:karma",
  - "options": {
  - "main": "apps/demo-libs/src/test.ts",
  - "tsConfig": "apps/demo-libs/tsconfig.spec.json",
  - "karmaConfig": "apps/demo-libs/karma.conf.js",
  - "polyfills": "apps/demo-libs/src/polyfills.ts",
  - "styles": [],
  - "scripts": [],
  - "assets": []
  - }
  }
  }
  },
  