make number of comparison in emojify() fewer (#4500)

fix style

"©"削除処理をemojione_lightに移動

app/javascript/mastodon/emojione_light.js

@@ -4,8 +4,10 @@
 const emojione = require('emojione');
 
 const mappedUnicode = emojione.mapUnicodeToShort();
+const excluded = ['®', '©', '™'];
 
 module.exports.unicodeMapping = Object.keys(emojione.jsEscapeMap)
+  .filter(c => !excluded.includes(c))
   .map(unicodeStr => [unicodeStr, mappedUnicode[emojione.jsEscapeMap[unicodeStr]]])
   .map(([unicodeStr, shortCode]) => ({ [unicodeStr]: [emojione.emojioneList[shortCode].fname, shortCode.slice(1, shortCode.length - 1)] }))
   .reduce((x, y) => Object.assign(x, y), { });