ENH: Improve the "Forum is moderated" template

## Is your feature request related to a problem?
**Please describe.**
Template uses a Table right now.
We did not want to change that for a minor version as that could be considered a breaking change.

## Describe the solution you'd like
Use correct HTML (div, headings etc. instead of a table)

## Describe alternatives you've considered
Nein

## Additional context
see: #999 
