add message

docs/development/development_guideline.md

@@ -156,7 +156,7 @@ IntelliJ allows you to [customize the data view in the Debug Tools](https://www.
 You can create your own NDArray renderer as follows:
 ![](img/custom_debug_view.png)
 
-Opening the IDE settings (`⌘ ,`), in *Java Type Renderer* section, you can:
+Opening the IDE settings (`⌘ ,`), in *Java Type Renderer* section, you can enable array display by:
 - Change the "Use following expression" field to [toDebugString(true)](https://javadoc.io/static/ai.djl/api/0.19.0/ai/djl/ndarray/NDArray.html#toDebugString-int-int-int-int-) to show NDArray content
 - Change the "Use following expression" field to something like [toDebugString(100, 10, 10, 20, true)](https://javadoc.io/static/ai.djl/api/0.19.0/ai/djl/ndarray/NDArray.html#toDebugString-int-int-int-int-)
 if you want to adjust the range of NDArray's debug output.