[BUG] Trying to train a model for classification gives a weird warning

[sarthakpati]

Describe the bug

When trying to train any classification model (and this is most prevalent for binary classification), the following UserWarning from sklearn pops up at every step per subject: y_pred contains classes not in y_true.

To Reproduce

Steps to reproduce the behavior:

1. Use any data for binary classification (TIL, EGFR, ...).
2. Try to train.
3. See the following warnings:

The ``converters`` are currently experimental. It may not support operations including (but not limited to) Functions in ``torch.nn.functional`` that involved data dimension

[SNIP!]

********************
Starting validation :
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C:\Projects\GaNDLF\venv\Lib\site-packages\sklearn\metrics\_classification.py:2399: UserWarning: y_pred contains classes not in y_true
  warnings.warn("y_pred contains classes not in y_true")

The first warning comes from this line.

Expected behavior

This warning should come up just once.

Media

N.A.

Environment information

GANDLF version: 0.0.20-dev
Git hash: 000ea17ecd2e018dafa2ecfe7a85c030bb4a02cb
Platform: Windows-10-10.0.22631-SP0
Machine: AMD64
Processor: Intel64 Family 6 Model 165 Stepping 2, GenuineIntel
Architecture: 64bit WindowsPE
Python environment:
  Version: 3.11.6
  Implementation: CPython
  Compiler: MSC v.1935 64 bit (AMD64)
  Build: main Oct  3 2023 10:29:11

Additional context

N.A.