Prevent onSelect callback when menu-list ListItem has property 'disabled' (#3042)

Co-authored-by: Stephen James <sjames@salesforce.com>

Author: rinkstiekema

components/utilities/menu-list/item.d.ts

@@ -5,6 +5,7 @@ declare module '@salesforce/design-system-react/components/utilities/menu-list/i
 		className?: any[] | Record<string, any> | string;
 		checkmark?: boolean;
 		data?: Record<string, any>;
+		disabled?: boolean;
 		divider?: 'top' | 'bottom';
 		href?: string;
 		id: string /*.isRequired*/;

components/utilities/menu-list/item.jsx

@@ -42,6 +42,7 @@ class ListItem extends React.Component {
 		]),
 		checkmark: PropTypes.bool,
 		data: PropTypes.object,
+		disabled: PropTypes.bool,
 		divider: PropTypes.oneOf(['top', 'bottom']),
 		href: PropTypes.string,
 		id: PropTypes.string.isRequired,
@@ -136,7 +137,7 @@ class ListItem extends React.Component {
 			EventUtil.trapImmediate(event);
 		}
 
-		if (this.props.onSelect) {
+		if (this.props.onSelect && !this.props.disabled) {
 			this.props.onSelect(this.props.index);
 		}
 	};