test: verify multiple init via well-known symbol

Re-`require()` the addon after clearing its cache to ensure that it is
re-initialized via the well-known symbol.

PR-URL: https://github.com/nodejs/node/pull/19875


Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>