chore: update node engines to next LTS (node 20 / npm 9)

Signed-off-by: John Molakvoæ <skjnldsv@protonmail.com>

package.json

@@ -65,7 +65,7 @@
     "webpack-node-externals": "^1.7.2"
   },
   "engines": {
-    "node": "^16.0.0",
-    "npm": "^7.0.0 || ^8.0.0"
+    "node": "^20.0.0",
+    "npm": "^9.0.0"
   }
 }