fix: logo improvements

[raphael0202]

• reduce number of k nearest neighbors to consider to 10 (instead of 100). We have a much better annotation coverage as at the beginning of the project, and 100 generates too many false positive, and prevent a correct brand logo detection.
• improve logo DB update CLI command

[codecov]

Codecov Report

Merging #1273 (81311a0) into main (dd6d81e) will decrease coverage by 0.02%.
Report is 1 commits behind head on main.
The diff coverage is 16.66%.

@@            Coverage Diff             @@
##             main    #1273      +/-   ##
==========================================
- Coverage   56.53%   56.51%   -0.02%     
==========================================
  Files          77       77              
  Lines        7465     7467       +2     
==========================================
  Hits         4220     4220              
- Misses       3245     3247       +2     

Files	Coverage Δ
robotoff/settings.py	91.94% <100.00%> (ø)
robotoff/cli/main.py	14.44% <0.00%> (-0.09%)	⬇️

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