Bump Jest dependencies to latest

[KaliedaRik]

What does this change?

This PR updates the Jest tool to the latest versions.

The primary aim of this update is to get rid of some Dependabot security alerts, and to lower technical debt going forward.

How to test

• Run yarn test locally - all tests should pass, as before.
• Run the PR in the CODE environment to see if the new system brakes any CI steps.
• Test in CODE - everything should operate as before.

[KaliedaRik]

Converting this PR to draft as we have failing tests.

Two test suites (in .ts files) pass with no issue:

The third fails, complaining that the jest.config.js hasn't been set up properly to handle Typescript and/or ES Modules. I don't believe these reports, given that two other test suites work fine:

The failure appears to be in a node_modules file - maybe forcing Jest to ignore the node_modules folder will fix this? (Jest claims it ignores that folder out-of-the-box ... but I'm not convinced this is entirely true)