Move definitions to cpp

[wujingyue]

tests/cpp/utils.h is a busy header file used by all tests.

[wujingyue]

!test

[github-actions]

Description

• Moved NVFuserTest methods to utils.cpp

• Updated utils.h to declare methods

• Added GTest::gtest to benchmark targets

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Changes walkthrough 📝

	Relevant files
Enhancement	utils.cpp Added NVFuserTest method definitions                                          tests/cpp/utils.cpp Added definitions for SetUp, TearDown, captureStdout, ensureStopCaptureStdout, and getCapturedStdout methods of NVFuserTest class. +64/-0    utils.h Declared NVFuserTest methods                                                          tests/cpp/utils.h Declared SetUp, TearDown, captureStdout, ensureStopCaptureStdout, and getCapturedStdout methods of NVFuserTest class. +5/-63
Configuration changes	CMakeLists.txt Added GTest::gtest to benchmark targets                                    CMakeLists.txt Added GTest::gtest to target_link_libraries for nvfuser_bench and nvfuser_multidevice_bench. +2/-0

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PR Reviewer Guide 🔍

Here are some key observations to aid the review process:

🧪 PR contains tests

⚡ Recommended focus areas for review Logging Initialization Ensure that c10::initLogging(); is the correct approach for initializing logging in this context. Verify if there are any side effects or performance implications. c10::initLogging(); Random Seed Handling Verify that the random seed handling logic is consistent with the rest of the codebase and that it correctly handles both provided and default seeds. at::manual_seed(getATenRandomSeed()); // If NVFUSER_TEST_ATEN_RANDOM_SEED is provided, use that for the ATen // random seed. Otherwise, use zero. If a test fails, this seed will be // printed. std::srand(getCRandomSeed()); GTest Dependency Ensure that adding GTest::gtest as a dependency is necessary and does not introduce any conflicts or unnecessary dependencies. GTest::gtest

[wujingyue]

Including tests/cpp/utils.cpp in source files without linking gtest was a bug. This change fixes it.