[bp/r51446][FIX] Code plugin w/ CodeMirror: we do not need to display vertical scrollbars in code listings - workaround for the "wrongly computed height with scrollbar" bug in CodeMirror

git-svn-id: file:///var/local/code.tiki.org/tikisvn/branches/12.x@51447 b456876b-0849-0410-b77d-98878d47e9d5