Index: wp-content/themes/twentythirteen/css/blocks.css
===================================================================
--- wp-content/themes/twentythirteen/css/blocks.css	(revision 53515)
+++ wp-content/themes/twentythirteen/css/blocks.css	(working copy)
@@ -271,7 +271,6 @@
 /* Table */
 
 .wp-block-table {
-	border-bottom: 1px solid #ededed;
 	border-collapse: collapse;
 	border-spacing: 0;
 	font-size: 14px;