Add Enum module support in PyTorchFileRecorder

[antimora]

Pull Request Template

Checklist

• Confirmed that run-checks all script has been executed.
• Made sure the book is up to date with changes in this PR.

Related Issues/PRs

Fixes #1431

Changes

1. Updated Deserializer logic for deserialize_enum
2. Added tests
3. Updated the book section

Testing

1. New unit tests
2. Rendered the book

[codecov]

Codecov Report

Attention: Patch coverage is 91.70306% with 19 lines in your changes are missing coverage. Please review.

Project coverage is 85.83%. Comparing base (093cbd3) to head (6662ed9).
Report is 1 commits behind head on main.

Files	Patch %	Lines
crates/burn-core/src/record/serde/de.rs	75.32%	19 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1436      +/-   ##
==========================================
+ Coverage   85.79%   85.83%   +0.03%     
==========================================
  Files         642      643       +1     
  Lines       71271    71494     +223     
==========================================
+ Hits        61150    61365     +215     
- Misses      10121    10129       +8     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[laggui]

LGTM! Just two minor typos/wording issue but approving in advance.

Thanks for working on this 🙂