busywork: upgrade some actions

[boneskull]

What is the Problem Being Solved?

I'm seeing this warning after builds:

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

Description of the Design

• Upgrade the mentioned actions

Security Considerations

Depends if we trust GitHub or not.

Scaling Considerations

n/a

Test Plan

n/a

Compatibility Considerations

n/a

Upgrade Considerations

This is unlikely to break anything.