Remove fixed width for admin block on dashboard

The fixed width breaks the dashboard on smaller screen sizes, as it overlaps with any blocks that may be to the right of it.

Resources/public/css/layout.css

@@ -66,10 +66,6 @@
     margin-left: 0px;
 }
 
-.sonata-bc table.sonata-ba-list {
-    width: 500px;
-}
-
 .sonata-bc div.sonata-ba-field-inline-table input.title {
     width: 100px;
 }