Stabilization: Fix update_etc_default_grub_manually - #15069

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: notiz-dev/github-action-json-property@a5a9c668b16513c737c3e1f8956772c99c73f6e8. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/