Add corona-effekt.orgatalk.de to list of example sites
The site offers a manually maintained list of LAN party cancellations due to
| [uggla.fr](https://uggla.fr) | https://github.com/uggla/blog |
| [NorthCon e.V.](https://verein.northcon.de/) | |
| [OrgaTalk wiki](https://wiki.orgatalk.de/) | https://github.com/orgatalk/wiki |
+| [Der Corona-Effekt](https://corona-effekt.orgatalk.de/) | https://github.com/orgatalk/corona-effekt |
