[primTorch] support one tensor and two scalars in _prims.where (#80146)
Fixes an issue of supporting two scalar arguments for `where` and other functions with similar set of arguments:
```
refs.where(a, 1, 0)
```
I had to skip `test_python_ref_executor` because the test causes a `Segmentation fault` when running with two scalars.
The issue https://github.com/csarofeen/pytorch/issues/1770 has been fixed https://github.com/csarofeen/pytorch/pull/1774, so we can lift the skip when its merged to the upstream.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/80146
Approved by: https://github.com/ngimel