fix #19500  Crash on deleting fermata

fix #19500
Crash on deleting fermata
The problem was in Score::removeElement, which was calling createPlayEvents also when the parent element was a rest. If then a fermata was removed from a rest, this was causing a crash because of chord->notes() (called in createPlayEvents) not properly defined when "chord" is a rest.
Score::addElement was already correct. I just copied and pasted the correction to the removeElelment function.