bug: try-except wrappers with TabPFN imports

[martilut]

This is a 🐛 bug fix.

Summary

Added try-except wrappers to TabPFN imports if fedot[extra] requirements are not installed

Context

Fixes #1402

[github-actions]

All PEP8 errors has been fixed, thanks ❤️

Comment last updated at Mon, 25 Aug 2025 18:30:47

[codecov]

Codecov Report

❌ Patch coverage is 25.00000% with 12 lines in your changes missing coverage. Please review.
✅ Project coverage is 80.29%. Comparing base (6cff9ed) to head (c5a019d).
⚠️ Report is 4 commits behind head on master.

Files with missing lines	Patch %	Lines
fedot/core/operations/evaluation/tabpfn.py	25.00%	12 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1403      +/-   ##
==========================================
- Coverage   80.39%   80.29%   -0.11%     
==========================================
  Files         150      150              
  Lines       10843    10858      +15     
==========================================
+ Hits         8717     8718       +1     
- Misses       2126     2140      +14     

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[martilut]

/fix-pep8

[VadimsAhmers]

Thanks for the changes! I've checked, and everything works as intended.