fix(Table): fix cell border not showing (#420)

Author: simonguo

docs/examples/FixedColumnTable.md

@@ -25,6 +25,7 @@ const App = () => {
       data={data}
       onScroll={handleScroll}
       cellBordered
+      bordered
       onRowClick={data => {
         console.log(data);
       }}

src/less/table.less

@@ -85,6 +85,7 @@
     white-space: normal;
     background: @body-background;
     transition: none;
+    box-sizing: border-box;
 
     &.first {
       border-left-width: 0;
@@ -101,6 +102,7 @@
     }
     &-content {
       padding: 8px;
+      box-sizing: border-box;
 
       .ellipsis();
     }