Affinity: Fix Gutenberg gallery block when images link to media files

- Adds an overflow: hidden setting to the anchor markup to prevent linked images from overflowing

affinity/blocks.css

@@ -51,6 +51,10 @@ p.has-drop-cap:not(:focus)::first-letter {
 	margin-left: auto;
 }
 
+.wp-block-gallery.is-cropped .blocks-gallery-item a {
+	overflow: hidden;
+}
+
 /* Quote */
 
 .wp-block-quote cite {