[bugfix] Cell: titleClass wrong type (#2780)

packages/cell/en-US.md

@@ -103,9 +103,9 @@ Vue.use(Cell).use(CellGroup);
 | is-link | Whether to show link icon | `Boolean` | `false` |
 | required | Whether to show required mark | `Boolean` | `false` |
 | arrow-direction | Can be set to `left` `up` `down` | `String` | - |
-| title-class | Title className | `String` | - |
-| value-class | Value className | `String` | - |
-| label-class | Label className | `String` | - |
+| title-class | Title className | `any` | - |
+| value-class | Value className | `any` | - |
+| label-class | Label className | `any` | - |
 
 ### Cell Event