lib: handle `throw undefined` in assert.throws()

And make `assert.doesNotThrow()` handle it as well.

Backport-PR-URL: https://github.com/nodejs/node/pull/19230
PR-URL: https://github.com/nodejs/node/pull/18029
Fixes: https://github.com/nodejs/node/issues/18027


Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Khaidi Chu <i@2333.moe>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>
Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>