JetStatistics divides by the wrong value
In line https://gitlab.idiap.ch/bob/bob.ip.gabor/-/blob/94bd69147ca4450ab9f975efab5ee31bbf3edefd/bob/ip/gabor/cpp/JetStatistics.cpp#L145 we divide by m_varAbs(j), but we'd need to divide by m_meanAbs(j).
In line https://gitlab.idiap.ch/bob/bob.ip.gabor/-/blob/94bd69147ca4450ab9f975efab5ee31bbf3edefd/bob/ip/gabor/cpp/JetStatistics.cpp#L145 we divide by m_varAbs(j), but we'd need to divide by m_meanAbs(j).