fix(fe/explore): prevent runtime error when editing Dataset-origin Chart with empty title (#32031)

Signed-off-by: hainenber <dotronghai96@gmail.com>

superset-frontend/src/explore/components/ExploreChartHeader/index.jsx

@@ -167,7 +167,7 @@ export const ExploreChartHeader = ({
     <>
       <PageHeaderWithActions
         editableTitleProps={{
-          title: sliceName,
+          title: sliceName ?? '',
           canEdit:
             !slice ||
             canOverwrite ||