(v6.x backport) test: remove node-tap lookalike
Manual backport of https://github.com/nodejs/node/pull/13707 to v6.x. This is another step towards backporting https://github.com/nodejs/node/pull/16938.
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
Manual backport of https://github.com/nodejs/node/pull/13707 to v6.x. This is another step towards backporting https://github.com/nodejs/node/pull/16938.