Add deform_conv2d as implemented in torchvision

[wingertge]

Add Deformable Convolution Layers v1/v2

Help would be welcome, I've been looking at the kernel so long I can no longer see my mistakes. Getting a few more pairs of eyes on it would be helpful.

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

A lot of resnet variants currently replace most conv2d layers with deform_conv2d. See torchvision docs

Changes

Adds the relatively popular deform_conv2d layer initially implemented in torchvision in 2021.

Testing

• Tested with comparison to pytorch output
• All tests passing

[wingertge]

Currently blocked on atomics being added to cubecl

[codecov]

Codecov Report

Attention: Patch coverage is 82.46020% with 683 lines in your changes missing coverage. Please review.

Project coverage is 85.67%. Comparing base (aa79e36) to head (04937ed).
Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
...urn-jit/src/kernel/conv/deform_conv_transpose2d.rs	51.41%	240 Missing ⚠️
crates/burn-autodiff/src/ops/module.rs	25.69%	214 Missing ⚠️
crates/burn-jit/src/kernel/conv/deform_conv2d.rs	45.41%	143 Missing ⚠️
crates/burn-core/src/nn/conv/deform_conv2d.rs	82.35%	27 Missing ⚠️
crates/burn-candle/src/ops/module.rs	0.00%	19 Missing ⚠️
crates/burn-tch/src/ops/module.rs	0.00%	19 Missing ⚠️
crates/burn-fusion/src/ops/module.rs	94.79%	10 Missing ⚠️
crates/burn-tensor/src/repr/operation.rs	72.72%	9 Missing ⚠️
crates/burn-tensor/src/tensor/ops/modules/base.rs	50.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2147      +/-   ##
==========================================
- Coverage   85.79%   85.67%   -0.13%     
==========================================
  Files         754      760       +6     
  Lines       95189    99082    +3893     
==========================================
+ Hits        81671    84888    +3217     
- Misses      13518    14194     +676     

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[wingertge]

Finally done and ready to review

[louisfd]

Just a few questions, otherwise very nice!

[louisfd]

LGTM