fix #23011: change channel broken

Two separate bugs here.  First caused staff text channel changes to be
applied at the wrong time.  Second prevented channel changes to "normal"
from working at all.
fix tests

No longer save explicit "normal" channel name in imported scores.  Also
remove explicit "normal" channel name from Cymbal in instruments.xml.
update importmidi/updateReference script
missed two tests
Merge pull request #683 from MarcSabatella/23011-change-channel

fix #23011: change channel broken