Improved the performance of RecallAtFixedPrecision for large batch sizes

[GlavitsBalazs]

What does this PR do?

Addresses #2041.

Before submitting

• Was this discussed/agreed via a Github issue? (no need for typos and docs improvements)
• Did you read the contributor guideline, Pull Request section?
• Did you make sure to update the docs?
• Did you write any new necessary tests?

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📚 Documentation preview 📚: https://torchmetrics--2042.org.readthedocs.build/en/2042/

[Borda]

@GlavitsBalazs nice, do you have a benchmark just to give an idea about the speedup? Also pls add entry in changelog

[codecov]

Codecov Report

Merging #2042 (2f1b332) into master (23c4e62) will decrease coverage by 38%.
The diff coverage is 95%.

Additional details and impacted files

@@           Coverage Diff            @@
##           master   #2042     +/-   ##
========================================
- Coverage      87%     49%    -38%     
========================================
  Files         279     279             
  Lines       15814   15828     +14     
========================================
- Hits        13718    7743   -5975     
- Misses       2096    8085   +5989     

[GlavitsBalazs]

@GlavitsBalazs nice, do you have a benchmark just to give an idea about the speedup? Also pls add entry in changelog

Ok. I've added the changelog entry.

My issue submission contains some basic measurements illustrating the speedup. Please let me know if these aren't enough. I'll create more benchmarks if necessary.

[SkafteNicki]

@GlavitsBalazs nice, do you have a benchmark just to give an idea about the speedup? Also pls add entry in changelog

Ok. I've added the changelog entry.

My issue submission contains some basic measurements illustrating the speedup. Please let me know if these aren't enough. I'll create more benchmarks if necessary.

@GlavitsBalazs I think the tests you done are fine, I am reposting here for future reference:

Batch Size	Before PR	After PR
100	~9	~8
1000	~20	~9
2000	~30	~10
5000	~70	~14
10000	~124	~19
100000	~1200	~110

[GlavitsBalazs]

Closes #2041