test: make status file names consistent

For some reason, the test/addons directory has a status file of
addon.status rather than addons.status. Make it consistent with other
directories.

PR-URL: https://github.com/nodejs/node/pull/37532


Reviewed-By: Richard Lau <rlau@redhat.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: James M Snell <jasnell@gmail.com>