fix: Workflow list page crashes for workflow rows without labels (#11195

)

Signed-off-by: Yuan Tang <terrytangyuan@gmail.com>

ui/src/app/workflows/components/workflows-row/workflows-row.tsx

@@ -88,7 +88,7 @@ export class WorkflowsRow extends React.Component<WorkflowsRowProps, WorkflowRow
                             </div>
                         </div>
                         {(this.props.columns || []).map(column => {
-                            const value = wf.metadata.labels[column.key];
+                            const value = wf.metadata?.labels[column.key];
                             return (
                                 <div key={column.name} className='columns small-1'>
                                     {value}