Don't use community layout for documentation pages

[sijie]

BUG REPORT

1. Please describe the issue you observed:

• What did you do?

The layout of documentation page is marked as community. when users navigate to this page, it is a bit difficult for the users to figure out where they are. https://bookkeeper.apache.org/docs/latest/index.html

• What did you expect to see?

It would be better to be something like this:

https://sijie.github.io/bookkeeper-staging-site/docs/latest/index.html

• What did you see instead?