README: use quotes in example, to divert users from shell globbing pitfalls
README: use quotes in example, to divert users from shell globbing pitfalls

Follow-up of https://github.com/nativefier/nativefier/issues/1159#issuecomment-827184112
jiahaog/Nativefier,jiahaog/Nativefier,jiahaog/Nativefier