chore: update string

src/locale/en-US.js

@@ -5,7 +5,7 @@ export default {
     'Displays the relations of an organization or similarly structured data. Starts at the top and allows for navigation through the hierachy.', // Description of chart, to be added to sense when native
   'Object.OrgChart.MaxData': 'The maximum data limit is reached. The tree may display incorrectly.',
   'Object.OrgChart.DummyRoot': 'Root root',
-  'Object.OrgChart.DummyWarn': 'No single root, root nodes inserted.',
+  'Object.OrgChart.DummyWarn': 'The data contains multiple root nodes.',
   'Object.OrgChart.CycleWarning': 'Data contains circular references, nodes are omitted.',
   'Object.OrgChart.MissingRoot': 'No root node, check your data for circular references.',
   'Object.OrgChart.LabelExpression': 'Label expression',