Grafana panel: Disk usage: Warning and critical threshold mixed up

[bzblf]

This issue respects the following points:

• [X] This is a bug, not a question or a setup/configuration issue.
• [X] This issue is not already reported on Github (I've searched it).
• [X] I use the latest release of the Monitoring Plugins (https://github.com/Linuxfabrik/monitoring-plugins/releases).
• [X] I agree to follow Monitoring Plugins's Code of Conduct.

Bug description

Relates to the grafana panel in disk-usage check The threshold for percent warning and critical (also the color) are mixed-up.

Steps to reproduce - Plugin call

The problem relates not the check itself
Look in Icinga and klick the `-percent warn` or `-percent crit` below the graph. You can see that the threshold is mixed up.

Steps to reproduce - Plugin Version

The problem relates not to the check itself

Steps to reproduce - Data

No explicit data needed. Look at the threshold warning and critical

Python version

No response

Environment

Doesn't relate to a specific OS

Application

No response

Python modules

No response

Additional info

It is a general Issue that belongs the grafana Panel