cubicweb-condor #2254730 remove cleanup_stale_runexecutions or introduce RunExecution concept [validation pending]

this actually belongs to pylos

orelse we may want to introduce a bare concept of RunExecution here ?

prioritynormal
typeenhancement
done in0.2.0
load0.100
load left0.000
closed by#b28aa7da12ab [commands] move cleanup routine back to pylos (closes #2254730)