fix(alert): add missing attr.role=alert

Author: xidedix

projects/coreui-angular/src/lib/alert/alert.component.ts

@@ -83,6 +83,14 @@ export class AlertComponent implements AfterContentInit {
   }
   private _fade = false;
 
+  /**
+   * Default role for alert. [docs]
+   * @type string
+   * @default 'alert'
+   */
+  @HostBinding('attr.role')
+  @Input() role = 'alert';
+
   /**
    * Set the alert variant to a solid.
    * @type string