[OPR-133]: Adds test verifying expected behavior when cancelling.
[OPR-133]: Adds test verifying expected behavior when cancelling.

In this case, an operation which is a dependency of another operation is cancelled before both operations are added to the queue. The operation which isn't cancelled, is still executed - expected behavior.

blg-andreasbraun/ProcedureKit,blg-andreasbraun/Operations,ProcedureKit/ProcedureKit,ProcedureKit/ProcedureKit,cezarywojcik/Operations,danthorpe/Operations,cezarywojcik/Operations,blg-andreasbraun/Operations,blg-andreasbraun/ProcedureKit,blg-andreasbraun/Operations,blg-andreasbraun/ProcedureKit,danthorpe/Operations,danthorpe/Operations,cezarywojcik/Operations,ProcedureKit/ProcedureKit