Adding unit test for finetuning from gnn

[WenkelF]

@DomInvivo the new unit test covers the following additional features:

• Finetuning from gnn (formerly only task head)
• Keeping & modifying modules of pretrained model after finetuning module
• Unfreezing additional pretrained depth

[codecov]

Codecov Report

Merging #433 (46c166b) into main (71182f4) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #433   +/-   ##
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  Coverage   64.74%   64.74%           
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  Files          89       89           
  Lines        8215     8215           
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  Hits         5319     5319           
  Misses       2896     2896           

Flag	Coverage Δ
unittests	64.74% <ø> (ø)

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Components	Coverage Δ
ipu	49.14% <ø> (ø)

[DomInvivo]

Great testing!

How long does it take to run the test?

[WenkelF]

It runs about 2 minutes

[WenkelF]

@DomInvivo I reduced the runtime of the test to 61 seconds by reducing the number of epochs of finetuning from 3 to 2 5ef06f2

[WenkelF]

@DomInvivo it now runs in <10 seconds after setting sample_size=100