[vue demo] Fix further spelling mistake
[vue demo] Fix further spelling mistake

Issue #6555

hackmdio/CodeMirror,dperetti/CodeMirror,pabloferz/CodeMirror,dperetti/CodeMirror,nightwing/CodeMirror,dperetti/CodeMirror,pabloferz/CodeMirror,wingify/CodeMirror,hackmdio/CodeMirror,nightwing/CodeMirror,wingify/CodeMirror,wingify/CodeMirror,nightwing/CodeMirror,hackmdio/CodeMirror,pabloferz/CodeMirror