Upgrading node to v20

[wjrosa]

Fixes STRIPE-446
Original PR #4264

Changes proposed in this Pull Request:

This is the main PR upgrading the extension Node version to 20. It is basically a recreation of #4264. The purpose is to keep the git history here cleaner, making it easier to review.

After upgrading many necessary packages, the ones we are upgrading here require Node 20, so they must go along with the main version change.

Testing instructions

• Checkout to this branch on your test environment (dev/node-20-main-upgrade)
• Confirm you can successfully build the frontend files for release: npm run build:webpack && npm run build:release
• Perform some basic smoke-testing on the frontend
• Confirm the frontend unit tests are still working: npm run test:js

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• Covered with tests (or have a good reason not to test in description ☝️)
• Tested on mobile (or does not apply)

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Comment

Post merge

• Added testing instructions to the Release Testing Instructions wiki page (or does not apply)
• Added the needs docs label (or does not apply)
• Included this PR in the Release Thread scope (or does not apply)

[diegocurbelo]

Thanks for working on this @wjrosa... Node 20 woohoo! 👏🏼 😄 👏🏼

The changes look good, and it works as expected:

• all checks pass
• tests run locally
• npm start and npm run build work (both after update and with a clean install)
• woorelease simulate generates a valid zip package

[diegocurbelo]

Why not use the same version as in the .nvmrc file?