chore: remove Singleton & replace getIApp with getApp (#5514)

src/singletons/Emotes.cpp

@@ -3,19 +3,10 @@
 namespace chatterino {
 
 Emotes::Emotes()
-{
-}
-
-void Emotes::initialize(Settings &settings, const Paths &paths)
 {
     this->emojis.load();
 
     this->gifTimer.initialize();
 }
 
-bool Emotes::isIgnoredEmote(const QString &)
-{
-    return false;
-}
-
 }  // namespace chatterino