doc: fix typos on n-api
Fixes a few typos I came across in the https://nodejs.org/dist/latest-v9.x/docs/api/n-api.html documentation. Thanks!
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
Fixes a few typos I came across in the https://nodejs.org/dist/latest-v9.x/docs/api/n-api.html documentation. Thanks!