enable specifying weights path for fid

[yuvalkirstain]

What does this PR do?

Fixes #<issue_number>

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?

PR review

In some places compute nodes do have access to internet, so it is important to enable loading metrics without internet access. This PR enables specifying the checkpoint path for FID.

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Make sure you had fun coding 🙃

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📚 Documentation preview 📚: https://torchmetrics--2867.org.readthedocs.build/en/2867/

[Borda]

I git it but still pls share motivation for this PR

[yuvalkirstain]

I did (perhaps not in the right place) - "In some places compute nodes do have access to internet, so it is important to enable loading metrics without internet access. This PR enables specifying the checkpoint path for FID."

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 1 line in your changes missing coverage. Please review.

Project coverage is 38%. Comparing base (3ff199c) to head (97db50a).
Report is 1 commits behind head on master.

❗ There is a different number of reports uploaded between BASE (3ff199c) and HEAD (97db50a). Click for more details.

HEAD has 2 uploads less than BASE

Flag	BASE (3ff199c)	HEAD (97db50a)
gpu	1	0
unittest	1	0

Additional details and impacted files

@@           Coverage Diff            @@
##           master   #2867     +/-   ##
========================================
- Coverage      69%     38%    -32%     
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  Files         346     332     -14     
  Lines       19133   18957    -176     
========================================
- Hits        13229    7109   -6120     
- Misses       5904   11848   +5944     

[lantiga]

Thanks!