Meson: Make spacing and #include ordering a bit more consistent

Not 100%, but a step forward.

Change-Id: I6957edbd24c1652b228a96a68424b857603aae45
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/mesonprojectmanager/settings/tools/toolitemsettings.cpp

@@ -24,11 +24,13 @@
 ****************************************************************************/
 
 #include "toolitemsettings.h"
+
 #include "tooltreeitem.h"
 #include "ui_toolitemsettings.h"
 
 namespace MesonProjectManager {
 namespace Internal {
+
 ToolItemSettings::ToolItemSettings(QWidget *parent)
     : QWidget(parent)
     , ui(new Ui::ToolItemSettings)