message: docs(changelog): 3.1.1
diff: @@ -16,6 +16,17 @@ Vant follows [Semantic Versioning 2.0.0](https://semver.org/lang/zh-CN/).
  ## Details
  +### [v3.1.1](https://github.com/youzan/vant/compare/v3.1.0...v3.1.1)
  +
  +`2021-06-27`
  +
  +**Feature**
  +
  +- Cell: add value slot [#8933](https://github.com/youzan/vant/issues/8933)
  +- CollapseItem: add label slot [#8934](https://github.com/youzan/vant/issues/8934)
  +- NoticeBar: add reset method [#8917](https://github.com/youzan/vant/issues/8917)
  +- Tabs: add nav-bottom slot [#8915](https://github.com/youzan/vant/issues/8915)
  +
  ### [v3.1.0](https://github.com/youzan/vant/compare/v3.1.0-beta.0...v3.1.0)
  `2021-06-22`
  