The BPMN XML schema definition seems to be missing at http://jmix.io/schema/bpm/bpmn

I get an error in my Intellij, because it cannot resolve:

https://www.jmix.io/schema/bpm/bpmn

If I go there it seems to be empty:

image

Therefore I get this error, which is not a problem, but I would like to get rid off:

image