Fix FeatureShare wrapper on GPU

[SkafteNicki]

What does this PR do?

Fixes #2339
Cached network are not a proper child module and is therefore currently not correctly moved to device.

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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--2348.org.readthedocs.build/en/2348/

[codecov]

Codecov Report

Merging #2348 (183a038) into master (84a6d3f) will decrease coverage by 34%.
The diff coverage is 0%.

Additional details and impacted files

@@           Coverage Diff            @@
##           master   #2348     +/-   ##
========================================
- Coverage      69%     35%    -34%     
========================================
  Files         303     303             
  Lines       17058   17059      +1     
========================================
- Hits        11760    5942   -5818     
- Misses       5298   11117   +5819