Add CUDA 13.2 support and drop unsupported 12.8/12.9 (pytorch#20440)

Add (13, 2) to SUPPORTED_CUDA_VERSIONS in install_utils.py and to the
cuda.yml build matrix. Remove 12.8 and 12.9, which are no longer
supported.

Author: Gasoonjia

.github/workflows/cuda.yml

@@ -2,6 +2,8 @@
 # This workflow tests whether ExecuTorch can be successfully built with CUDA support
 # across different CUDA versions (12.6, 13.0) using the command:
 #   ./install_executorch.sh
+# 
+# Intentionally skipped CUDA version 13.2 check due to ci image unsupported.
 #
 # Note: ExecuTorch automatically detects the system CUDA version using nvcc and
 # installs the appropriate PyTorch wheel. No manual CUDA/PyTorch installation needed.

install_utils.py

@@ -16,9 +16,8 @@
 # Format: tuple of (major, minor) version numbers
 SUPPORTED_CUDA_VERSIONS = (
     (12, 6),
-    (12, 8),
-    (12, 9),
     (13, 0),
+    (13, 2),
 )