Fix the docs page 404 link (#145)

* fix 404 link

* Update themes/docsy/layouts/docs/baseof.html

Co-authored-by: 吴晟 Wu Sheng <wu.sheng@foxmail.com>

Co-authored-by: Zhenxu Ke <kezhenxu94@163.com>
Co-authored-by: 吴晟 Wu Sheng <wu.sheng@foxmail.com>
diff --git a/themes/docsy/layouts/docs/baseof.html b/themes/docsy/layouts/docs/baseof.html
index c897e97..d38d8a7 100644
--- a/themes/docsy/layouts/docs/baseof.html
+++ b/themes/docsy/layouts/docs/baseof.html
@@ -183,7 +183,7 @@
                         docs
                       </button>
                       <div class="dropdown-menu">
-                        <a class="dropdown-item" target="_blank" href="https://github.com/apache/skywalking-kubernetes/tree/4.0.0">v0.4.0</a>
+                        <a class="dropdown-item" target="_blank" href="https://github.com/apache/skywalking-kubernetes/tree/v4.0.0">v4.0.0</a>
                       </div>
                     </div>