issue #1971: SO line characteristics fail if purchasing disabled

https://github.com/xtuple/xtuple/blob/6b40092460dd36c4c04df61f3dfafec51f6e12dc/enyo-client/application/source/views/workspace.js#L2218 can simply be removed because it's already here: https://github.com/xtuple/xtuple/blob/4_8_x/enyo-client/extensions/source/purchasing/client/views/workspace.js#L464