Add CLIP score

[SkafteNicki]

What does this PR do?

Fixes #1311
Adds CLIP score which will be our first multi modal metric :D

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

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[codecov]

Codecov Report

Merging #1314 (56dc6f7) into master (e4014f4) will decrease coverage by 0%.
The diff coverage is 46%.

Additional details and impacted files

@@          Coverage Diff           @@
##           master   #1314   +/-   ##
======================================
- Coverage      87%     87%   -0%     
======================================
  Files         204     208    +4     
  Lines       11621   11695   +74     
======================================
+ Hits        10100   10134   +34     
- Misses       1521    1561   +40     

[stancld]

Cool to have the first multimodal metric in torchmetrics. Just a few nitpicks, otherwise great work! 👍

[stancld]

Superb work! 💪

[Borda]

@SkafteNicki sorry, it was my bad to ask for var with min Trnformer version while they are now used only in one domain so there is no case of misconfiguration...