package: set minimum required node.js engine version to 20

Author: jooy2

package-lock.json

@@ -39,7 +39,7 @@
     "test:linux": "npm run build:pre && xvfb-run --auto-servernum --server-args='-screen 0, 1280x960x24' -- playwright test"
   },
   "engines": {
-    "node": ">=18.0.0"
+    "node": ">=20.0.0"
   },
   "dependencies": {
     "electron-log": "^5.4.1",