Remove UTF-8 charset warning from news

[danopz]

• I have read the CONTRIBUTING.md and followed the provided tips

Explain the Problem

Currently when we are running Nextcloud with MySQL without utf8mb4 enabled we are showing a notice in the notifications for this: Non UTF-8 charset for MySQL/MariaDB database detected!.
Now that this warning is added to the server (nextcloud/server#14398, nextcloud/server#14857) setup check directly we could probably remove it from the news app - we shouldn't duplicate warnings here.

I would just like to know what you think. If decided I will create a pull request for that.

[SMillerDev]

Nice find, I'd be happy to get rid of this. Please look at documentation too when you remove it 👍

[Grotax]

Thanks