Fix emoji not showing up in button component

discord/components.py

@@ -143,9 +143,13 @@ class Button(Component):
         }
         if self.custom_id:
             payload['custom_id'] = self.custom_id
+
         if self.url:
             payload['url'] = self.url
 
+        if self.emoji:
+            payload['emoji'] = self.emoji.to_dict()
+
         return payload  # type: ignore
 
 def _component_factory(data: ComponentPayload) -> Component: