Replace static_casts by QOverload where possible

Mainly to get rid of the QProcess::finished deprecation warning.

Also adjust coding style in the surrounding connects when needed.

Change-Id: I12f9b248c7974b892c4a069356e578e80f8c59e9
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/cppeditor/cppcodemodelinspectordialog.cpp

@@ -1389,7 +1389,7 @@ CppCodeModelInspectorDialog::CppCodeModelInspectorDialog(QWidget *parent)
     connect(m_snapshotView, &FilterableView::filterChanged,
             this, &CppCodeModelInspectorDialog::onSnapshotFilterChanged);
     connect(m_ui->snapshotSelector,
-            static_cast<void (QComboBox::*)(int)>(&QComboBox::currentIndexChanged),
+            QOverload<int>::of(&QComboBox::currentIndexChanged),
             this, &CppCodeModelInspectorDialog::onSnapshotSelected);
     connect(m_ui->docSymbolsView, &QTreeView::expanded,
             this, &CppCodeModelInspectorDialog::onSymbolsViewExpandedOrCollapsed);