Channel admin option to disable @here and similar for a channel

Some teams find the use of broadcast aliases like @here disruptive /
distracting and sometimes abused for things that do not require immediate
attention. While individual users can tweak their notification preference
per channel and outright mute a channel to avoid being notified for things
like @here, some teams may prefer to also have the option as a channel
admin to outright disable the use of @here in a channel.

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*Derek Gottlieb*
Sangoma | Cloud Janitor | Engineering / Switchvox Cloud Dev