UI: Fix bug where password property won't save

In my recent update to add a "show" button to the passworded text
property, I neglected to connect the edit widget to
WidgetInfo::ControlChanged, so it isn't able to detect when the text is
changed by the user.

obs/properties-view.cpp

@@ -215,6 +215,9 @@ QWidget *OBSPropertiesView::AddText(obs_property_t *prop, QFormLayout *layout,
 
 		label = new QLabel(QT_UTF8(obs_property_description(prop)));
 		layout->addRow(label, subLayout);
+
+		connect(edit, SIGNAL(textEdited(const QString &)),
+				info, SLOT(ControlChanged()));
 		return nullptr;
 	}