Fix media captions in bubble layout (#28480)

Author: tulir

res/css/views/rooms/_EventBubbleTile.pcss

@@ -334,7 +334,6 @@ Please see LICENSE files in the repository root for full details.
 
         .mx_MImageBody {
             width: 100%;
-            height: 100%;
 
             .mx_MImageBody_thumbnail.mx_MImageBody_thumbnail--blurhash {
                 position: unset;