Replace mocha with Node.js' built-in test runner

As of Node.js 16.17.0, Node.js now provides a built-in test runner which is strikingly similar to Mocha and thus effectively replaces it (at least for what we need it for). The built-in test runner has been further improved in Node.js 18 and 19. We should explore using it in the harness in place of Mocha (and Chai).

By switching the TCK harness to use Node.js' built-in test runner (possibly removing the use of Chai as well), we can avoid having to bundle external libraries, simplify the operation of the TCK, and make it easier to maintain in the long run.

Refer to https://nodejs.org/api/test.html to find the documentation for the test runner.