[FIX] antialising in PreProcessor

[felixdittrich92]

This PR:

• fix inconsistency of antialising in PreProcessor

[codecov]

Codecov Report

Merging #1324 (43516d8) into main (8245706) will decrease coverage by 0.03%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #1324      +/-   ##
==========================================
- Coverage   95.75%   95.72%   -0.03%     
==========================================
  Files         154      154              
  Lines        6902     6902              
==========================================
- Hits         6609     6607       -2     
- Misses        293      295       +2     

Flag	Coverage Δ
unittests	95.72% <100.00%> (-0.03%)	⬇️

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Files Changed	Coverage Δ
doctr/models/preprocessor/pytorch.py	96.42% <100.00%> (ø)

... and 1 file with indirect coverage changes