fix outline offset

Author: dmirgaev

packages/devextreme-scss/scss/widgets/base/dataGrid/_index.scss

@@ -485,7 +485,7 @@ $datagrid-text-stub-background-image-path: null !default;
     right: 0;
     outline: 2px solid;
     outline-color: $datagrid-focused-border-color;
-    outline-offset: -2px;
+    outline-offset: -1px;
     z-index: 4; // should overlap sticky column cells
     pointer-events: none;
     background-color: transparent;