Fix ErrorModal title

ts/components/ErrorModal.stories.tsx

@@ -17,7 +17,7 @@ const i18n = setupI18n('en', enMessages);
 const createProps = (overrideProps: Partial<PropsType> = {}): PropsType => ({
   buttonVariant: overrideProps.buttonVariant ?? undefined,
   description: overrideProps.description ?? '',
-  title: overrideProps.title ?? '',
+  title: Object.hasOwn(overrideProps, 'title') ? overrideProps.title : '',
   i18n,
   onClose: action('onClick'),
 });
@@ -48,3 +48,14 @@ export function CustomStrings(): JSX.Element {
     />
   );
 }
+
+export function NoTitle(): JSX.Element {
+  return (
+    <ErrorModal
+      {...createProps({
+        title: null,
+        description: 'This is a fun error!',
+      })}
+    />
+  );
+}

ts/components/ErrorModal.tsx

@@ -40,7 +40,7 @@ export function ErrorModal(props: PropsType): JSX.Element {
       modalName="ErrorModal"
       i18n={i18n}
       onClose={onClose}
-      title={title == null ? undefined : i18n('icu:ErrorModal--title')}
+      title={title == null ? undefined : title || i18n('icu:ErrorModal--title')}
       modalFooter={footer}
     >
       <div className="module-error-modal__description">