image resolution to low

[derrabauke]

The linked image on https://github.com/projectcaluma/docs/blob/8db5ad34cf71d639b1db16b0975ee1e303d17991/introduction/evaluating-caluma/what-problems-does-caluma-solve.md is not recognizable. We need to provide it in a better quality.

@czosel do you know where this image came from? Should we just create an own example? It's quite generic.

[czosel]

I don’t remember, my guess would be a google search for “simple BPMN example” or similar. I think creating our own example would be good 👍