docs: update route config for new resizing example (#5229)

* start column sizing guide

* add new example to config

Author: KevinVandy

docs/config.json

@@ -229,6 +229,10 @@
           "to": "examples/react/column-sizing",
           "label": "Column Sizing"
         },
+        {
+          "to": "examples/react/column-resizing-performant",
+          "label": "Performant Column Resizing"
+        },
         {
           "to": "examples/react/column-visibility",
           "label": "Column Visibility"