Supress warnings in MeanAveragePrecision when intended

[SkafteNicki]

What does this PR do?

Fixes #2490

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• Did you make sure to update the docs?
• Did you write any new necessary tests?

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📚 Documentation preview 📚: https://torchmetrics--2501.org.readthedocs.build/en/2501/

[codecov]

Codecov Report

Merging #2501 (c4ca271) into master (9e83421) will decrease coverage by 33%.
The diff coverage is 100%.

Additional details and impacted files

@@           Coverage Diff            @@
##           master   #2501     +/-   ##
========================================
- Coverage      69%     36%    -33%     
========================================
  Files         307     307             
  Lines       17396   17396             
========================================
- Hits        11981    6301   -5680     
- Misses       5415   11095   +5680