tools: fix docs and run known_issues by default

- Updates `test/README.md` with new suites
- Fixes some outdated `IGNORED_SUITES` listings
- Allows for `test/known_issues` suite to be run by default

PR-URL: https://github.com/nodejs/node/pull/21910


Reviewed-By: Vse Mozhet Byt <vsemozhetbyt@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Lance Ball <lball@redhat.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>