Fix enterEvent signature for Qt5/Qt6 compatibility

tools/chatgui/src/emojipanel.cpp

@@ -46,7 +46,11 @@ public:
     const QString &unicode() const { return m_data.unicode; }
 
 protected:
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
     void enterEvent(QEnterEvent *e) override {
+#else
+    void enterEvent(QEvent *e) override {
+#endif
         QPushButton::enterEvent(e);
         if (m_icon && m_icon->isValid()) {
             m_hovered = true;