Allow for additional classNames without override

Author: Tomdango

src/components/warning-callout/WarningCallout.tsx

@@ -11,18 +11,21 @@ const WarningCallout: React.FC<WarningCalloutProps> = ({
   children,
   labelProps,
   ...rest
-}) => (
-  <div className={classNames('nhsuk-warning-callout', className)} {...rest}>
-    {label ? (
-      <h3
-        className={classNames('nhsuk-warning-callout__label', labelProps?.className)}
-        {...labelProps}
-      >
-        {label}
-      </h3>
-    ) : null}
-    {children}
-  </div>
-);
+}) => {
+  const { labelClassName: className, ...restLabelProps } = labelProps || {};
+  return (
+    <div className={classNames('nhsuk-warning-callout', className)} {...rest}>
+      {label ? (
+        <h3
+          className={classNames('nhsuk-warning-callout__label', labelClassName)}
+          {...restLabelProps}
+        >
+          {label}
+        </h3>
+      ) : null}
+      {children}
+    </div>
+  );
+}
 
 export default WarningCallout;