doc: replace U+00A0 with U+0020
Replace NO-BREAK SPACE (U+00A0) with SPACE (U+0020) in doc/api/net.md
.
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
Replace NO-BREAK SPACE (U+00A0) with SPACE (U+0020) in doc/api/net.md
.