Update README.md (#6071)

The last ROCM 6.2 build was November 22nd, after that date new builds use ROCM 6.2.4.

The builds from the new URL have been tested and work without problems.

README.md

@@ -147,7 +147,7 @@ AMD users can install rocm and pytorch with pip if you don't have it already ins
 
 This is the command to install the nightly with ROCm 6.2 which might have some performance improvements:
 
-```pip install --pre torch torchvision torchaudio --index-url https://download.pytorch.org/whl/nightly/rocm6.2```
+```pip install --pre torch torchvision torchaudio --index-url https://download.pytorch.org/whl/nightly/rocm6.2.4```
 
 ### NVIDIA