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
fix #24657: save correct mixer info for instrument change
fix TravisCI artifact upload. See https://github.com/travis-ci/travis-artifacts/issues/23
fix #24678
fix #23111 split-measure shifts following spanners
fix #23648: Hook of note with value of eighth or less misaligned in Emmentaler
Merge pull request #699 from AntonioBL/splitmeasure_slurs

fix #23111 split-measure shifts following spanners
add test for #23111
fix test
draw text frame
Merge branch 'master' of github.com:musescore/MuseScore
start testing of text facility
fix #24001: add "Text Style..." to context menu

open text style dialog, pre-set to text style of selected element
handle chord symbols
add simple MusicXML iotest to mtest
fix MusicXML vertical positioning
suppress "Text Style" in menu for unstyled text

Chord symbols treated as styled for this purpose, since the chord symbol
text style is always used.