Gallery block: use image caption as fallback for alt text. (#26082)

packages/block-library/src/gallery/save.js

@@ -39,23 +39,17 @@ export default function save( { attributes } ) {
  href = image.link;
  break;
  }
- // The image should only have an aria-label if it's within a link and has no alt text.
- const imageLabel =
- ! image.alt && image.caption && href
- ? image.caption
- : null;
 
  const img = (
  <img
  src={ image.url }
- alt={ image.alt }
+ alt={ image.alt !== '' ? image.alt : image.caption }
  data-id={ image.id }
  data-full-url={ image.fullUrl }
  data-link={ image.link }
  className={
  image.id ? `wp-image-${ image.id }` : null
  }
- aria-label={ imageLabel || null }
  />
  );