When calling defineEventProbes to redefine the probes in a target, if the event classes are the same we don't redefine the class, rather we try to define a new one, causing a linkageError as the class already exists. This has the side effect of not redefining the class, so if the user wished to change the description, or some other aspect of the event class it isn't done. We should redefine the class in these cases.