New bot for monthly statistics

[xsaschako]

Motivation / Current Behaviour

We want to post statistics and gather them monthly.

Enhancement description

I'll ad a bot which posts it into the mattermost for now.

Additional context

No response

Checklist

• Attached labels, especially loc:: or model:: labels.
• Linked to project

[kilianvolmer]

Bot works (probably), but we do not want to merge it to main.