docs(IllustratedMessage): add link to ui5wc IllustrationMessageType enum docs (#7422)

Author: Lukas742

packages/main/src/webComponents/IllustratedMessage/IllustratedMessage.mdx

@@ -19,6 +19,10 @@ import { IllustratedMessage } from './index';
 
 <ControlsWithNote of={ComponentStories.Default} />
 
+## Illustrations
+
+You can find all available illustrations [here](https://sap.github.io/ui5-webcomponents/components/fiori/enums/IllustrationMessageType/).
+
 ## Fully customizable title
 
 <MessageStrip