Make FP8 BMM output contiguous (#3270)

Summary:
Pull Request resolved: #3270

X-link: facebookresearch/FBGEMM#370

Make fp8 bmm output contiguous as [silu_mul](https://fburl.com/code/sa1faq0w) requests output tensor of fp8 bmm stride(-1) to be 1. This Diff fixes the issue

Reviewed By: jspark1105

Differential Revision: D64811808

fbshipit-source-id: e0f213f24fbf8bf989576371af1e2ada4cafbfb1

Author: jiawenliu64

fbgemm_gpu/experimental/gen_ai/src/quantize/cutlass_extensions/f8f8bf16_rowwise_batched.cu

@@ -448,7 +448,7 @@ at::Tensor handle_transposition(
           BIAS_DTYPE>(
           WQ.transpose(1, 2), XQ.transpose(1, 2), w_scale, x_scale, bias, out);
     }
-    return out_.transpose(1, 2);
+    return out_.transpose(1, 2).contiguous();
   }
 }