fix(@angular-devkit/build-angular): remove left-over experimentalRollupPass option

Author: alan-agius4

packages/angular_devkit/build_angular/src/browser/schema.json

@@ -384,11 +384,6 @@
         "use-credentials"
       ]
     },
-    "experimentalRollupPass": {
-      "type": "boolean",
-      "description": "Concatenate modules with Rollup before bundling them with Webpack.",
-      "default": false
-    },
     "allowedCommonJsDependencies": {
       "description": "A list of CommonJS packages that are allowed to be used without a build time warning.",
       "type": "array",