[libcalamaresui] Replace a superfluous lambda

- The whole method body can be a lot on its own, and since
   loadModules() does nothing but single-shot the lambda,
   call it from outside instead.

src/calamares/CalamaresApplication.cpp

@@ -39,6 +39,7 @@
 #include <QDesktopWidget>
 #include <QDir>
 #include <QFileInfo>
+#include <QTimer>
 
 
 CalamaresApplication::CalamaresApplication( int& argc, char* argv[] )
@@ -354,7 +355,7 @@ CalamaresApplication::initView()
     connect( m_moduleManager, &Calamares::ModuleManager::modulesLoaded, this, &CalamaresApplication::initViewSteps );
     connect( m_moduleManager, &Calamares::ModuleManager::modulesFailed, this, &CalamaresApplication::initFailed );
 
-    m_moduleManager->loadModules();
+    QTimer::singleShot( 0, m_moduleManager, &Calamares::ModuleManager::loadModules );
 
     m_mainwindow->move( this->desktop()->availableGeometry().center() - m_mainwindow->rect().center() );
 

src/libcalamaresui/modulesystem/ModuleManager.cpp

@@ -182,7 +182,6 @@ findCustomInstance( const Settings::InstanceDescriptionList& customInstances, co
 void
 ModuleManager::loadModules()
 {
-    QTimer::singleShot( 0, this, [this]() {
     QStringList failedModules = checkDependencies();
     Settings::InstanceDescriptionList customInstances = Settings::instance()->customModuleInstances();
 
@@ -308,7 +307,6 @@ ModuleManager::loadModules()
     {
         emit modulesLoaded();
     }
-    } );
 }
 
 void

src/libcalamaresui/modulesystem/ModuleManager.h

@@ -79,8 +79,9 @@ public:
     Module* moduleInstance( const QString& instanceKey );
 
     /**
-     * @brief loadModules initiates the asynchronous module loading operation.
+     * @brief loadModules does all of the module loading operation.
      * When this is done, the signal modulesLoaded is emitted.
+     * It is recommended to call this from a single-shot QTimer.
      */
     void loadModules();