Fix failing unit tests on BMG

[joeatodd]

BMG has alignment restrictions which don't seem to exist on PVC. This PR:

• Sets alignment-friendly shapes in various GEMM unit tests
• Uses padding (i.e. pitched tensor) to fix some block copy unit tests

[FMarno]

If the test didn't meet the precondition of the BMG implementation, the test should probably have resulted in a skip when they hit this can_implement check:

cutlass-sycl/test/unit/gemm/device/gemm_testbed_3x.hpp

Line 3005 in 4814348

cutlass::Status status = gemm_op.can_implement(arguments);

I'm guessing they didn't. Would now be a good time to update can_implement?

[joeatodd]

If the test didn't meet the precondition of the BMG implementation, the test should probably have resulted in a skip when they hit this can_implement check:

cutlass-sycl/test/unit/gemm/device/gemm_testbed_3x.hpp

Line 3005 in 4814348

cutlass::Status status = gemm_op.can_implement(arguments);

I'm guessing they didn't. Would now be a good time to update can_implement?

I believe @t4c1 has done just that in #323