Change to vertical navbar layout for secondary navbar for repo/user/admin settings (#24246)
Co-Author: @wxiaoguang
This is the first step of #24229. And this PR will only includes html
changes, and followed by other PRs that fine tune css and change to
submenus.
After:
Admin Level
<img width="1400" alt="Screen Shot 2023-04-21 at 10 07 16"
src="https://user-images.githubusercontent.com/17645053/233523870-f848b61d-056a-4b41-9760-a9a49fea1fe8.png">
User Level
<img width="1422" alt="Screen Shot 2023-04-21 at 10 07 23"
src="https://user-images.githubusercontent.com/17645053/233523878-979adb20-a657-43d9-99a6-ad414010c0ef.png">
Repo Level
<img width="1404" alt="Screen Shot 2023-04-21 at 10 07 07"
src="https://user-images.githubusercontent.com/17645053/233523863-337440bd-c03a-4dfd-87fa-cef40300bfe0.png">
---------
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>