cubicweb-worker #5337880 provide an interface & mechanism to abort a task [done]

By e.g. sending a "signal" to the task, it should then kill the relevant subprocess.

prioritynormal
typeenhancement
done in4.0.0
load left0.000
closed by#d0c87da6122f Provide a mechanism to abort a running task (from any instance)
patchProvide a mechanism to abort a running task (from any instance) [applied]