test: resolve process.setegid error on Ubuntu

When the tests are run as root in Ubuntu, process.setegid is called with
'nobody' as an argument. This throws an error in Ubuntu. This is because
in Ubuntu the equivalent of 'nobody' group is named as 'nogroup'.

This commit sets egid to 'nobody' first and if it throws a `group id
does not exist` error, it attempts to set egid to 'nogroup'. If it still
causes an error, the error is thrown.

PR-URL: https://github.com/nodejs/node/pull/19757
Refs: https://github.com/nodejs/node/issues/19594


Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: James M Snell <jasnell@gmail.com>