Buttons need a loading state

[telion2]

The Buttons here https://telekom.github.io/scale/?path=/docs/components-button--standard do not feature a loading state.

The Loading State means, that the Button is disabled and shows a loading spinner. (At least that's how we did it until now.)
This means that colours need to be adjusted, disbaled = true and a spinner Icon is displayed.

The Use-Case can be a generic "Save" Button that sends changed Data to the backend and waits until the backend responds with success order Error.

Alternatively I guess I can implement it myself, but in that case, the design might be inconsistent among the telekom platforms. But if scale supports that in the future, then implementing it will be for naught. But since we use that feature now, we cannot switch to scale buttons.