build: don't mark language-service package as sideEffect free (#22808)

we are not sure if this is the case and we don't need this package to
be optimized at the moment.

PR Close #22808

packages/language-service/package.json

@@ -13,6 +13,5 @@
   },
   "ng-update": {
     "packageGroup": "NG_UPDATE_PACKAGE_GROUP"
-  },
-  "sideEffects": false
+  }
 }