Fix torch.conj for zero-dimensional sparse coo matrix (#59553)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/59553
Added a test for 0x0 sparse coo input for sparse_unary_ufuncs.
This test fails for `conj` on master.
Modified `unsupportedTypes` for test_sparse_consistency, complex dtypes
pass, but float16 doesn't pass for `conj` because `to_dense()` doesn't
work with float16.
Fixes https://github.com/pytorch/pytorch/issues/59549
Test Plan: Imported from OSS
Reviewed By: jbschlosser
Differential Revision: D28968215
Pulled By: anjali411
fbshipit-source-id: 44e99f0ce4aa45b760d79995a021e6139f064fea
