ryubuilder: update for newer sphinx

Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
fix overflowed table width

Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
ja: sw_test_tool: Add descriptions about group table

Signed-off-by: Yuichi Ito <ito.yuichi0@gmail.com>