Update docs markdown file weight to make it clear (#23909)

For Docusaurus, it needs a meta data named `sidebar_position`, so we
copy all `weight` under `menu/sidebar` as top meta key.

docs/content/doc/help/search.en-us.md

@@ -2,11 +2,11 @@
 date: "2019-11-12T16:00:00+02:00"
 title: "Search"
 slug: "search"
-weight: 4
+weight: 1
 toc: false
 draft: false
 sitemap:
-  priority : 0.1
+  priority : 1
 layout: "search"
 ---