build: fix IBM i build with Python 3.9
Python 3.9 on IBM i returns "os400" for sys.platform
.
Refs: https://github.com/nodejs/node/pull/46739 Refs: https://github.com/nodejs/build/pull/3358
cc @nodejs/platform-ibmi
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
Python 3.9 on IBM i returns "os400" for sys.platform
.
Refs: https://github.com/nodejs/node/pull/46739 Refs: https://github.com/nodejs/build/pull/3358
cc @nodejs/platform-ibmi