Update actions to use Nodejs v20

[ZIMkaRU]

This PR updates GH Actions to use Nodejs v20

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Context: https://github.blog/changelog/2023-09-22-github-actions-transitioning-from-node-16-to-node-20/
Our current warnings: https://github.com/bitfinexcom/bfx-report-electron/actions/runs/7913595670

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Basic changes:

• Update gh actions to resolve deprecation warnings
• Point coactions/setup-xvfb gh action to exact commit to have required nodejs ver under hood: resolved here Use node20 coactions/setup-xvfb#23
• Fix disabling auto-update when build release. Minore improvement for beta releases

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TODO:

• GH Action dorny/test-reporter does not still support actions/upload-artifact@v4 required for Nodejs 20 migration. And to upload test reports needs to use v3 with Nodejs v16 which will show one related warning actions/upload-artifact & actions/download-artifact v4 support dorny/test-reporter#363
  So here we are waiting for dorny/test-reporter changes to have the last resolved
  No breaking changes here and can be merged freely

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Everything has been tested on own fork:

• https://github.com/ZIMkaRU/bfx-report-electron/actions/runs/8017162965
• https://github.com/ZIMkaRU/bfx-report-electron/actions/runs/8017417802

[ezewer]

looks good to me!