Translate "Outlook 365" reactions into Discourse reactions

[sam (Sam Saffron)]

The feature request for this is here:

Disallow Outlook emoji reactions

Continuing the discussion from Translate "Outlook 365" reactions into Discourse reactions: Since Discourse cannot process Outlook reactions at this time, we can add a header to suppress Outlook clients from sending them. According to @trs80 and How to Disable Outlook reactions - o365info, This will reduce noise from Outlook users on Discourse forums. In the future if we add support for them, we can remove the suppression header from topic emails.

This seems way simpler, and I will go ahead and give it a shot.

Remapping feels extremely complex and error prone. It is probably healthier just to disable the feature.