convert : add split() to LoraTorchTensor in LoRA converter (#22832)

* convert : add split() method to LoraTorchTensor

* Fix python type-check

* Fix flake8 Lint

* fix: handle positional dim arg in torch.split dispatch

* Fix type-check again

* Fix type-checks

* Remove unit test per reviewers feedback

* work around ty deficiency

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Co-authored-by: Sigbjørn Skjæret <sigbjorn.skjaeret@scala.com>