Remove node 12 from package.json engines

Support for node 12 was already officially dropped here: ember-codemods#490

Author: gitKrystan

package.json

@@ -82,7 +82,7 @@
     "typescript": "^4.9.5"
   },
   "engines": {
-    "node": "12.* || >= 14"
+    "node": ">= 14.*"
   },
   "publishConfig": {
     "registry": "https://registry.npmjs.org"