[Bug]: Faulty L2 normalization

[iamrobzy]

There seems to be a bug in the L2 normalization coco_similiarity.py file (utils/metrics/coco_similarity.py, lines 217-221)

# l2 normalize
xg=xg/np.sqrt((xg**2).sum())       
yg=yg/np.sqrt((yg**2).sum())       
xd=xd/np.sqrt((xd**2).sum())       
yd=xd/np.sqrt((yd**2).sum())  

Line 221 (the last line above) should be normalizing yd, but is instead normalizing xd. The correction is:

yd=yd/np.sqrt((yd**2).sum())