test: refactor stavenote.js to fix CI build (appveyor)
test: refactor stavenote.js to fix CI build (appveyor)

seems like something in the appveyor setup doesn't recognize ||=
which led the builds to fail with syntax error

opensheetmusicdisplay/opensheetmusicdisplay,opensheetmusicdisplay/opensheetmusicdisplay,opensheetmusicdisplay/opensheetmusicdisplay