Breaking: Set Node-Version to >=v16.20

[Trickfilm400]

Changes

• Updated (dev-)dependencies
  • is-ip cannot be updated to the latest version due to ESModule incompatibility, but there are also no important changes
  • updated to new mocha configuration file
• changed one test result because return value changed
  • I'm not sure if this is an upstream change, but it seems so
• Updated node version in the GitHub actions CI
• removed dox dependency, as it seems unused
• Set required nodejs engine version to >=16.20.0, the latest v16 LTS release

Notes

• Browser Tests are still failing, but they did before all of the updates, so the updates should be unrelated to this issue
• Should be deprecate the old npm package versions because of the vulnerabilities these versions had?

Based on / Follow Up PR: #306 (comment)

[keithamus]

This is v5.0.0-alpha1. I'd like to get this using ESM before releasing 5 proper, inline with Chai 5.