[Glitch] Fix custom emoji selection

Port f28715d370 to glitch-soc

Signed-off-by: Claire <claire.github-309c@sitedethib.com>

app/javascript/flavours/glitch/features/compose/components/emoji_picker_dropdown.jsx

@@ -228,7 +228,7 @@ class EmojiPickerMenuImpl extends PureComponent {
 
   handleClick = (emoji, event) => {
     if (!emoji.native) {
-      emoji.native = emoji.colons;
+      emoji.native = `:${emoji.id}:`;
     }
     if (!(event.ctrlKey || event.metaKey)) {