test: increase n-api constructor coverage

Add tests to validate that properties marked as static
are available through the class as opposed to instances

PR-URL: https://github.com/nodejs/node/pull/13124


Reviewed-By: Jason Ginchereau <jasongin@microsoft.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Hitesh Kanwathirtha <digitalinfinity@gmail.com>