REMOVE old QT<= 5.14 code

Ubuntu 22.04  use qt 1.15.3.
In the code is still used qt code <5.10.
A cleanup was done by removing qT code version used in ubuntu 18.04.

src/Mod/Material/App/MaterialValue.cpp

@@ -26,7 +26,6 @@
 #endif
 
 #include <App/Application.h>
-#include <Base/QtTools.h>
 #include <Base/Quantity.h>
 #include <Gui/MetaTypes.h>
 

src/Mod/Material/Gui/DlgDisplayPropertiesImp.cpp

@@ -199,16 +199,6 @@ void DlgDisplayPropertiesImp::setupFilters()
 
 void DlgDisplayPropertiesImp::setupConnections()
 {
-#if QT_VERSION < QT_VERSION_CHECK(5, 14, 0)
-    connect(d->ui.changeMode,
-            qOverload<const QString&>(&QComboBox::activated),
-            this,
-            &DlgDisplayPropertiesImp::onChangeModeActivated);
-    connect(d->ui.changePlot,
-            qOverload<const QString&>(&QComboBox::activated),
-            this,
-            &DlgDisplayPropertiesImp::onChangePlotActivated);
-#else
     connect(d->ui.changeMode,
             &QComboBox::textActivated,
             this,
@@ -217,7 +207,6 @@ void DlgDisplayPropertiesImp::setupConnections()
             &QComboBox::textActivated,
             this,
             &DlgDisplayPropertiesImp::onChangePlotActivated);
-#endif
     connect(d->ui.spinTransparency,
             qOverload<int>(&QSpinBox::valueChanged),
             this,