Update dependencies (fixed)

[10xLaCroixDrinker]

Fixes the issues in #105

Updating to tap@18 resolved the issue of tests failing when running via tap CLI. However, tap migrated its coverage collection to c8 which uses v8's built-in coverage tooling, and deleting entries from the require cache in the test suite broke the coverage reporting. So I added nyc for coverage collection. I enabled the use-spawn-wrap option in nyc because without it the tests in child processes broke due of how nyc affects stdio in child processes. This does mean though that the coverage from those tests is not counted now. Hence the added istanbul ignore statement in index.js.

dependency-check is deprecated, so I replaced it with knip. There was a reference to a non-existent npm run deps script so I added knip there, and I added scripts to allow standard to be run on its own.

I also updated the scripts that test individual versions of debug so they wouldnt modify the package.json or lockfile and gave them a cleanup script to restore the previously installed version of debug on completion.