Fixed comma appended to username completion when not at the beginning of the message (#3060)

Co-authored-by: pajlada <rasmus.karlsson@pajlada.com>

src/widgets/splits/Split.cpp

@@ -306,6 +306,11 @@ ChannelView &Split::getChannelView()
     return *this->view_;
 }
 
+SplitInput &Split::getInput()
+{
+    return *this->input_;
+}
+
 void Split::updateInputPlaceholder()
 {
     if (!this->getChannel()->isTwitchChannel())