chore(eslint-config-graphql)!: drop support for Node.js v16 and v18

BREAKING CHANGE: Node.js v16 and v18 are no longer supported

refs #191

Author: literat

packages/eslint-config-graphql/package.json

@@ -20,7 +20,7 @@
     "url": "https://github.com/lmc-eu/code-quality-tools/issues"
   },
   "engines": {
-    "node": "^16 || ^18 || >=20"
+    "node": ">=20"
   },
   "publishConfig": {
     "access": "public"