DistributionEditor now vertical

GUI/View/Instrument/DistributionEditor.cpp

@@ -165,7 +165,7 @@ DistributionEditor::DistributionEditor(const QString& title,
                                        BeamDistributionItem* item, bool allow_distr)
     : QGroupBox(title, parent)
 {
-    auto* hLayout = new QHBoxLayout(this);
+    auto* hLayout = new QVBoxLayout(this);
     m_selector = new DistributionSelector(mean_config, distributions, this, item, allow_distr);
     hLayout->addWidget(m_selector);
     hLayout->setSpacing(50);