fix umb-table styling

src/Umbraco.Web.UI.Client/src/less/components/umb-table.less

@@ -3,11 +3,12 @@
     display: flex;
     flex-direction: column;
     position: relative;
-    border: 1px solid @gray-8;
     background: @white;
     flex-wrap: nowrap;
     justify-content: space-between;
     min-width: auto;
+    box-shadow: 0 1px 1px 0 rgba(0,0,0,0.16);
+    border-radius: 3px;
 }
 
 .umb-table.umb-table-inactive {
@@ -45,7 +46,6 @@ input.umb-table__input {
 
 // Table Head Styles
 .umb-table-head {
-    background-color: @white;
     font-size: 14px;
     font-weight: bold;
 }