Add a link to the icon list.

I had to ask in Discord for this link, this will help people looking for icons in the future.

main.ts

@@ -17,6 +17,7 @@ export default class MyPlugin extends Plugin {
 		await this.loadSettings();
 
 		// This creates an icon in the left ribbon.
+		// Most icons from https://lucide.dev/icons/ can be used.
 		const ribbonIconEl = this.addRibbonIcon('dice', 'Sample Plugin', (evt: MouseEvent) => {
 			// Called when the user clicks the icon.
 			new Notice('This is a notice!');