Prefix postfix args in clone for multitask

[SkafteNicki]

What does this PR do?

Fixes #2325
Nice to have feature. Similar to the way it is done in metric collection. These are the only two metrics that return dicts therefore it should not be necessary to add anywhere else.

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• Did you write any new necessary tests?

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📚 Documentation preview 📚: https://torchmetrics--2330.org.readthedocs.build/en/2330/

[codecov]

Codecov Report

Merging #2330 (e16feac) into master (35bdeb6) will decrease coverage by 34%.
Report is 1 commits behind head on master.
The diff coverage is 27%.

Additional details and impacted files

@@           Coverage Diff            @@
##           master   #2330     +/-   ##
========================================
- Coverage      69%     35%    -34%     
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  Files         305     305             
  Lines       17149   17164     +15     
========================================
- Hits        11832    5982   -5850     
- Misses       5317   11182   +5865