Sheet: modernize C++: use equals default

src/Mod/Spreadsheet/Gui/AppSpreadsheetGui.cpp

@@ -63,8 +63,6 @@ namespace SpreadsheetGui {
             initialize("This module is the SpreadsheetGui module."); // register with Python
         }
 
-        ~Module() override {}
-
     private:
         Py::Object open(const Py::Tuple& args)
         {

src/Mod/Spreadsheet/Gui/DlgSettingsImp.cpp

@@ -43,10 +43,7 @@ DlgSettingsImp::DlgSettingsImp( QWidget* parent )
 /** 
  *  Destroys the object and frees any allocated resources
  */
-DlgSettingsImp::~DlgSettingsImp()
-{
-    // no need to delete child widgets, Qt does it all for us
-}
+DlgSettingsImp::~DlgSettingsImp() = default;
 
 void DlgSettingsImp::saveSettings()
 {

src/Mod/Spreadsheet/Gui/SheetTableView.cpp

@@ -459,10 +459,7 @@ void SheetTableView::removeColumns()
     Gui::Command::doCommand(Gui::Command::Doc, "App.ActiveDocument.recompute()");
 }
 
-SheetTableView::~SheetTableView()
-{
-
-}
+SheetTableView::~SheetTableView() = default;
 
 void SheetTableView::updateCellSpan()
 {

src/Mod/Spreadsheet/Gui/SpreadsheetView.cpp

@@ -550,9 +550,7 @@ SheetViewPy::SheetViewPy(SheetView *mdi)
 {
 }
 
-SheetViewPy::~SheetViewPy()
-{
-}
+SheetViewPy::~SheetViewPy() = default;
 
 Py::Object SheetViewPy::repr()
 {

src/Mod/Spreadsheet/Gui/Workbench.cpp

@@ -63,9 +63,7 @@ Workbench::Workbench()
 {
 }
 
-Workbench::~Workbench()
-{
-}
+Workbench::~Workbench() = default;
 
 void Workbench::activated()
 {