A subscriber issues a UNSUBSCRIBE_ANNOUNCES message to a publisher
indicating it is no longer interested in ANNOUNCE and UNANNOUNCE messages for
the specified track namespace prefix.
The format of UNSUBSCRIBE_ANNOUNCES is as follows:
UNSUBSCRIBE_ANNOUNCES Message {
Type (i) = 0x14,
Length (i),
Track Namespace Prefix (tuple)
}
-
Track Namespace Prefix: As defined in Section 7.13.