feat(language-service): update supported range of node versions (#41544)

Update the supported range of node versions for Angular.  Angular now
supports node >=12.14.1 to <16.0.0, dropping support for Node v10.

PR Close #41544

packages/language-service/package.json

@@ -6,6 +6,9 @@
   "typings": "./index.d.ts",
   "author": "angular",
   "license": "MIT",
+  "engines": {
+    "node": ">=12.14.1 <16.0.0"
+  },
   "repository": {
     "type": "git",
     "url": "https://github.com/angular/angular.git",