[MusicXML import] [trunk] import error: 31a-Directions.xml missing dashes and bracket

File 31a-Directions.xml in Reinhold Kainhofers unofficial MusicMXL testsuite imports without dashes and bracket. These could be implemented in MuseScore as lines, with style dash for dashes and lines with hooks on both ends for bracket.

See also #14825: [MusicXML import] [1.2] import error: 31a-Directions.xml missing dashes and bracket.