Macros: Merge macrooptionswidget.{h,cpp} into macrooptionspage.cpp

Change-Id: I4493d781a503dde252ae6ad4d705e378b5b0ed51
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/macros/macrooptionspage.h

@@ -5,8 +5,7 @@
 
 #include <coreplugin/dialogs/ioptionspage.h>
 
-namespace Macros {
-namespace Internal {
+namespace Macros::Internal {
 
 class MacroOptionsPage final : public Core::IOptionsPage
 {
@@ -14,5 +13,4 @@ public:
     MacroOptionsPage();
 };
 
-} // namespace Internal
-} // namespace Macros
+} // Macros::Internal