[ROCM] Upgrade torch to 2.6

[SageMoore]

Now that we have the torch 2.6 upgrade finished, we can also move to torch 2.6 on ROCm. This PR just updates the torch version the requirements/rocm-build.txt

Here are the lm-eval results for 'meta-llama/Llama-3.1-8B-Instruct running with V1

|Tasks|Version|     Filter     |n-shot|  Metric   |   |Value|   |Stderr|
|-----|------:|----------------|-----:|-----------|---|----:|---|-----:|
|gsm8k|      3|flexible-extract|     5|exact_match|↑  |0.794|±  |0.0181|
|     |       |strict-match    |     5|exact_match|↑  |0.774|±  |0.0187|

V0 Get's similar results

The unit testing situation is a bit complicated here. AFAIK the AMD CI runs with the docker container which is currently pinned to a 2.7 nightly. If there are any specific unit tests that would be good to run locally, please let me know.

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