GitLab

* add functions to get number of params which require grad, get optimizer group for parameters and get learning rates of param groups to trainer.py

* add tests and raise ValueError when optimizer is None

* add second layer to test and freeze its weigths

* check if torch is available before running tests

* use decorator to check if torch is available
Co-authored-by: amyeroberts <22614925+amyeroberts@users.noreply.github.com>

* fix test indentation
Co-authored-by: Zach Mueller <muellerzr@gmail.com>

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Co-authored-by: amyeroberts <22614925+amyeroberts@users.noreply.github.com>
Co-authored-by: Zach Mueller <muellerzr@gmail.com>