Before this commit, executing the `/history` command in a livechat
would do nothing. Indeed, the message was sent on the wrong target
through the bus so the history request was never received by the
visitor client. This commit fixes the issue by sending the notification
on the channel instead of the channel uuid.
closesodoo/odoo#135254
Signed-off-by: Didier Debondt (did) <did@odoo.com>