Inform about Zeebe async behaviour

[jonathanlukas]

Is your feature request related to a problem? Please describe.

Currently, the converter informs about the removal of async-before and async-after flags.

But: The radical change is that synchronous execution is not possible anymore.

Describe the solution you'd like

There should be a TASK on synchronous executed activities to check whether the implementation relies on the synchronous behaviour as this does not work anymore.

Describe alternatives you've considered

no

Additional context

https://camunda.slack.com/archives/C0PPM4F46/p1694098573814359?thread_ts=1694075085.767609&cid=C0PPM4F46

[ingorichtsmeier]

We should consider to output this only once on the process level. It may confuse people when they get a lot of false positive messages here.