test: fix V8 test on big-endian machines
Ref: https://github.com/nodejs/node/pull/12143#issuecomment-291131159
/cc @targos
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
Ref: https://github.com/nodejs/node/pull/12143#issuecomment-291131159
/cc @targos