doc: move Mesteery to collaborators
cc @nodejs/tsc @Mesteery
Refs: https://github.com/nodejs/node/issues/41216 Refs: https://github.com/nodejs/node/pull/41543
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
cc @nodejs/tsc @Mesteery
Refs: https://github.com/nodejs/node/issues/41216 Refs: https://github.com/nodejs/node/pull/41543