QFileSystemModel: properly align file size column

The file size column was not properly horizontally aligned. The model
only returned Qt::AlignRight with no horizontal alignment. This lead
to a top alignment within QStyle::alignedRect().

Task-number: QTBUG-64098
Change-Id: Iaef30200a63bd0975c88a67d0af2eb1d5254f588
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>

src/widgets/dialogs/qfilesystemmodel.cpp

@@ -747,7 +747,7 @@ QVariant QFileSystemModel::data(const QModelIndex &index, int role) const
         break;
     case Qt::TextAlignmentRole:
         if (index.column() == 1)
-            return Qt::AlignRight;
+            return QVariant(Qt::AlignTrailing | Qt::AlignVCenter);
         break;
     case FilePermissions:
         int p = permissions(index);