fix test sdpa converter test cpp build issue

[lanluo-nvidia]

Description

Got the following build issue in dlfw cpp tests:

[› |                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  core/runtime/execute_engine.cpp: In lambda function:
  core/runtime/execute_engine.cpp:399:43: error: 'struct at::cuda::CUDAGraph' has no member named 'has_graph_exec'; did you mean 'bool
  at::cuda::CUDAGraph::has_graph_exec_'? (not accessible from this context)
    399 |           if (!compiled_engine->cudagraph.has_graph_exec()) {
        |                                           ^~~~~~~~~~~~~~
  In file included from ./core/runtime/TRTEngine.h:11,
                   from ./core/runtime/runtime.h:11,
                   from core/runtime/execute_engine.cpp:9:
  bazel-out/k8-fastbuild/bin/external/+_repo_rules3+libtorch/_virtual_includes/ATen/ATen/cuda/CUDAGraph.h:109:8: note: declared protected here
    109 |   bool has_graph_exec_ = false;
        |        ^~~~~~~~~~~~~~~
  Target //tests/core/conversion/converters:test_scaled_dot_product_attention failed to build
  Use --verbose_failures to see the command lines of failed build steps.
  INFO: Elapsed time: 36.046s, Critical Path: 23.08s
  INFO: 8394 processes: 8312 internal, 82 processwrapper-sandbox.
  ERROR: Build did NOT complete successfully](`url`)

tests/core/conversion/converters/test_scaled_dot_product_attention.cpp:92:3: error: expected primary-expression before '(' token
2026-07-13T17:46:28.998059Z 01E    92 |   ASSERT_FALSE(torch::isnan(jit_results[0]).any().item<bool>());
2026-07-13T17:46:28.998061Z 01E       |   ^~~~~~~~~~~~
2026-07-13T17:46:28.998062Z 01E tests/core/conversion/converters/test_scaled_dot_product_attention.cpp:92:23: error: 'isnan' is not a member of 'torch'
2026-07-13T17:46:28.998064Z 01E    92 |   ASSERT_FALSE(torch::isnan(jit_results[0]).any().item<bool>());
2026-07-13T17:46:28.998066Z 01E       |                       ^~~~~
2026-07-13T17:46:28.998068Z 01E tests/core/conversion/converters/test_scaled_dot_product_attention.cpp:92:23: note: suggested alternatives:
2026-07-13T17:46:28.998070Z 01E bazel-out/k8-dbg/bin/external/+_repo_rules+libtorch/_virtual_includes/c10_cuda/c10/util/complex_utils.h:43:6: note:   'std::isnan'
2026-07-13T17:46:28.998072Z 01E    43 | bool isnan(const c10::complex<T>& v) {
2026-07-13T17:46:28.998074Z 01E       |      ^~~~~
2026-07-13T17:46:28.998075Z 01E bazel-out/k8-dbg/bin/external/+_repo_rules+libtorch/_virtual_includes/ATen/ATen/ops/isnan.h:28:19: note:   'at::isnan'
2026-07-13T17:46:28.998077Z 01E    28 | inline at::Tensor isnan(const at::Tensor & self) {
2026-07-13T17:46:28.998079Z 01E       |                   ^~~~~
2026-07-13T17:46:28.998080Z 01E bazel-out/k8-dbg/bin/external/+_repo_rules+libtorch/_virtual_includes/ATen/ATen/core/interned_strings.h:351:1: note:   'c10::aten::isnan'
2026-07-13T17:46:28.998082Z 01E   351 | FORALL_NS_SYMBOLS(DEFINE_SYMBOL)
2026-07-13T17:46:28.998084Z 01E       | ^~~~~~~~~~~~~~~~~
2026-07-13T17:46:28.998085Z 01E bazel-out/k8-dbg/bin/external/+_repo_rules+libtorch/_virtual_includes/ATen/ATen/ops/isnan_ops.h:19:18: note:   'at::_ops::isnan'
2026-07-13T17:46:28.998088Z 01E    19 | struct TORCH_API isnan {
2026-07-13T17:46:28.998089Z 01E       |                  ^~~~~
2026-07-13T17:46:28.998090Z 01E bazel-out/k8-dbg/bin/external/+_repo_rules+libtorch/_virtual_includes/ATen/ATen/ops/isnan_native.h:21:22: note:   'at::native::isnan'
2026-07-13T17:46:28.998093Z 01E    21 | TORCH_API at::Tensor isnan(const at::Tensor & self);
2026-07-13T17:46:28.998094Z 01E       |                      ^~~~~
2026-07-13T17:46:28.998096Z 01E tests/core/conversion/converters/test_scaled_dot_product_attention.cpp:92:56: error: expected primary-expression before 'bool'
2026-07-13T17:46:28.998098Z 01E    92 |   ASSERT_FALSE(torch::isnan(jit_results[0]).any().item<bool>());
2026-07-13T17:46:28.998100Z 01E       |                                                        ^~~~
2026-07-13T17:46:28.998102Z 01E tests/core/conversion/converters/test_scaled_dot_product_attention.cpp:92:56: error: expected ')' before 'bool'
2026-07-13T17:46:28.998104Z 01E tests/core/conversion/converters/test_scaled_dot_product_attention.cpp:92:3: note: to match this '('
2026-07-13T17:46:28.998106Z 01E    92 |   ASSERT_FALSE(torch::isnan(jit_results[0]).any().item<bool>());
2026-07-13T17:46:28.998108Z 01E       |   ^~~~~~~~~~~~
2026-07-13T17:46:28.998109Z 01E tests/core/conversion/converters/test_scaled_dot_product_attention.cpp:92:3: error: expected ')' before ';' token
2026-07-13T17:46:28.998111Z 01E    92 |   ASSERT_FALSE(torch::isnan(jit_results[0]).any().item<bool>());
2026-07-13T17:46:28.998113Z 01E       |   ^~~~~~~~~~~~
2026-07-13T17:46:28.998114Z 01E tests/core/conversion/converters/test_scaled_dot_product_attention.cpp:93:23: error: 'isnan' is not a member of 'torch'
2026-07-13T17:46:28.998116Z 01E    93 |   ASSERT_FALSE(torch::isnan(trt_results[0]).any().item<bool>());

Fixes # (issue)

Type of change

Please delete options that are not relevant and/or add your own.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist:

• My code follows the style guidelines of this project (You can use the linters)
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas and hacks
• I have made corresponding changes to the documentation
• I have added tests to verify my fix or my feature
• New and existing unit tests pass locally with my changes
• I have added the relevant labels to my PR in so that relevant reviewers are notified

[narendasan]

LGTM