Github Actions Workflows should be updated to use Node.js 20

Description of issue

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system_test (niscope)
Node.js 16 actions are deprecated. Please update the following actions to use Node.js 20: actions/checkout@v3, codecov/codecov-action@v3. For more information see: https://github.blog/changelog/2023-09-22-github-actions-transitioning-from-node-16-to-node-20/.

We should update our configuration to use Node.js 20, before support for Node.js 16 is dropped entirely.

The configuration for this can be found in .github\workflows\github_actions_aws_*.yml (the * is a wildcard not part of a filename).
The steps look like:

    steps:
      - name: checkout repository
        uses: actions/checkout@v3
      - name: upload coverage
        uses: codecov/codecov-action@v3

• For codecov-action, the issue was addressed in the v4 release
  • Arguments to the action have changes, so see the README
  • There's some mixed messaging that suggests we could go back to Tokenless uploading (PRs made from forks to the upstream public repos will support tokenless), but based on my reading of things, I don't think that's the case. It'll give us intermittent upload failures, again
• For checkout, the issue was addressed in the v4 release
  • For usage, see the README

Start with the .github/workflows/github_actions_aws_*.yml files and inspect every actions/checkout and codecov/codecov-action step. Read the checkout v4 and Codecov v4 READMEs before updating their versions and any changed arguments. Done means the workflows use Node.js 20-compatible actions and coverage uploads continue to work.