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/installation/database-preparation.en-us.md

@@ -9,7 +9,7 @@ menu:
   sidebar:
     parent: "installation"
     name: "Database preparation"
-    weight: 5
+    weight: 10
     identifier: "database-prep"
 ---