[Bugfix] torch nightly version in ROCm installation guide

[terrytangyuan]

This fixes the following error when using this guide:

Looking in indexes: https://download.pytorch.org/whl/nightly/rocm6.2
ERROR: Could not find a version that satisfies the requirement torch==2.6.0.dev20240918 (from versions: 2.6.0.dev20241024+rocm6.2, 2.6.0.dev20241026+rocm6.2, 2.6.0.dev20241027+rocm6.2, 2.6.0.dev20241028+rocm6.2, 2.6.0.dev20241029+rocm6.2, 2.6.0.dev20241030+rocm6.2, 2.6.0.dev20241031+rocm6.2, 2.6.0.dev20241101+rocm6.2, 2.6.0.dev20241102+rocm6.2, 2.6.0.dev20241103+rocm6.2, 2.6.0.dev20241104+rocm6.2, 2.6.0.dev20241105+rocm6.2, 2.6.0.dev20241106+rocm6.2, 2.6.0.dev20241107+rocm6.2, 2.6.0.dev20241108+rocm6.2, 2.6.0.dev20241109+rocm6.2, 2.6.0.dev20241110+rocm6.2, 2.6.0.dev20241111+rocm6.2, 2.6.0.dev20241112+rocm6.2, 2.6.0.dev20241113+rocm6.2, 2.6.0.dev20241114+rocm6.2, 2.6.0.dev20241115+rocm6.2, 2.6.0.dev20241116+rocm6.2, 2.6.0.dev20241117+rocm6.2, 2.6.0.dev20241118+rocm6.2, 2.6.0.dev20241119+rocm6.2, 2.6.0.dev20241120+rocm6.2, 2.6.0.dev20241121+rocm6.2, 2.6.0.dev20241122+rocm6.2)
ERROR: No matching distribution found for torch==2.6.0.dev20240918

References:

• https://download.pytorch.org/whl/nightly/torch/
• https://download.pytorch.org/whl/nightly/rocm6.2

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