Don't allow the city info grid to become squeezed

The grid layout showing city output info in the city screen allowed rows to
shrink below their preferred size, which created overlap when there were many
units in a city. Not setting the row weights to 0 prevents this with no
apparent negative consequence.

Closes longturn#665.

client/gui-qt/citydlg.cpp

@@ -1046,7 +1046,6 @@ city_info::city_info(QWidget *parent) : QWidget(parent)
     qlt[iter]->setFont(*small_font);
     qlt[iter]->setProperty(fonts::notify_label, "true");
     info_grid_layout->addWidget(qlt[iter], iter, 1);
-    info_grid_layout->setRowStretch(iter, 0);
   }
   setLayout(info_grid_layout);
 }