change :emoji: style emojis to direct unicode form
change :emoji: style emojis to direct unicode form

This enables iOS (and likely other systems) to display the emoji properly in notifications, rather than just the ":text form:". It also helps show users that they can use any emoji of their choice in the alerts.
bchanudet/OctoPrint-Octorant,bchanudet/OctoPrint-Octorant