Fix testcases that depends on triton (#7731)
Error:
```
> fp16_matmul.skip_autotune()
E AttributeError: 'NoneType' object has no attribute 'skip_autotune'
ops/transformer/inference/test_attention.py:37: AttributeError
```
due to `fp16_matmul` is None when deepspeed.HAS_TRITON is `False`
Signed-off-by: Artem Kuzmitckii <artem.kuzmitckii@amd.com>
