Refactor folder3d to avoid complex-structure (C901) issue

[samet-akcay]

📝 Description

• Provide a clear summary of the changes and the issue that has been addressed.
• 🛠️ Fixes 🔨 Refactor - make_folder3d_dataset is too complex (16 > 15)RuffC901 #1826

✨ Changes

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• 🐞 Bug fix (non-breaking change which fixes an issue)
• 🔨 Refactor (non-breaking change which refactors the code base)
• 🚀 New feature (non-breaking change which adds functionality)
• 💥 Breaking change (fix or feature that would cause existing functionality to not work as expected)
• 📚 Documentation update
• 🔒 Security update

✅ Checklist

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• 📋 I have summarized my changes in the CHANGELOG and followed the guidelines for my type of change (skip for minor changes, documentation updates, and test enhancements).
• 📚 I have made the necessary updates to the documentation (if applicable).
• 🧪 I have written tests that support my changes and prove that my fix is effective or my feature works (if applicable).

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[codecov]

Codecov Report

Attention: Patch coverage is 90.00000% with 1 line in your changes missing coverage. Please review.

Project coverage is 80.78%. Comparing base (e7e6cb8) to head (70c1ef0).
Report is 1 commits behind head on main.

Files	Patch %	Lines
src/anomalib/data/depth/folder_3d.py	90.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2185   +/-   ##
=======================================
  Coverage   80.78%   80.78%           
=======================================
  Files         248      248           
  Lines       10859    10849   -10     
=======================================
- Hits         8772     8764    -8     
+ Misses       2087     2085    -2     

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