Fix precision issue in pairwise euclidean distance

[SkafteNicki]

What does this PR do?

Fixes #1351

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• Did you write any new necessary tests?

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[codecov]

Codecov Report

Merging #1352 (0e08bfa) into master (7d77daf) will decrease coverage by 56%.
The diff coverage is 100%.

Additional details and impacted files

@@           Coverage Diff            @@
##           master   #1352     +/-   ##
========================================
- Coverage      87%     30%    -56%     
========================================
  Files         210     210             
  Lines       11825   11807     -18     
========================================
- Hits        10249    3583   -6666     
- Misses       1576    8224   +6648