chore: Constrained matplotlib version

[fg-mindee]

This PR attempts to fix the matplotlib issue upon installation in #412 by avoiding the latest release (of today).

Any feedback is welcome!

[codecov]

Codecov Report

Merging #413 (9829e42) into main (86daa0f) will increase coverage by 0.02%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main     #413      +/-   ##
==========================================
+ Coverage   95.80%   95.83%   +0.02%     
==========================================
  Files          91       91              
  Lines        3838     3838              
==========================================
+ Hits         3677     3678       +1     
+ Misses        161      160       -1     

Flag	Coverage Δ
unittests	95.83% <ø> (+0.02%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...dels/detection/differentiable_binarization/base.py	91.97% <0.00%> (+0.61%)	⬆️

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