Fix pruning with non tensor params

[aminst]

What does this PR do?

This pull request fixes the pruning problem made when a model includes non-tensor parameters.
The previous code added all parameters when parameters_to_prune was not provided. However, this causes problems when parameters are not Tensors. I added a line so just Tensor parameters will be included.

Fixes #10835

Does your PR introduce any breaking changes? If yes, please list them.

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[aminst]

Hi everyone, I think the added check will fix the problem (I checked this using a model from one of my projects). However, I have not yet been able to write a test addressing the change.
I need to instantiate a module with non Tensor params to test the change, which I couldn't do. Can anyone help? Thanks a lot.

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