update node 16->20

[undg]

This will shush warning mentioned in issue https://github.com/garygrossgarten/github-action-scp/issues/46

ANNOTATIONS
! Node.js 16 actions are deprecated. Please update the following actions to use Node.js 20: garygrossgarten/github-action-scp@release. For more information see: https://github.blog/changelog/2023-09-22-github-actions-transitioning-from-node-16-to-node-20/.

I've tested it with my action:

name: CD

on:
  push:
    branches: [ main ]
  workflow_dispatch:

jobs:
  build:
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v4
      - run: yarn
      - run: yarn build

      - name: Copy folder content recursively to remote
        # @TODO (undg) 2024-06-17: use fork for now
        uses: undg/github-action-scp@master
        # uses: garygrossgarten/github-action-scp@release
        with:
          local: _site
          remote: ${{ secrets.SSH_PATH }}
          host: ${{ secrets.SSH_HOST }}
          port: ${{ secrets.SSH_PORT }}
          username: ${{ secrets.SSH_USER }}
          password: ${{ secrets.SSH_PWD }}