[LifetimeSafety] Fix Python path for Windows compatibility (#166291)

Fix Python virtual environment paths for Windows in the Lifetime Safety
Analysis benchmark

### What changed?

- Added conditional path setting for the Python executable in the
virtual environment based on the platform
- For Windows, use `Scripts/python` path
- For other platforms, use `bin/python` path
- Updated the commands that use the Python virtual environment to use
the platform-specific path

### How to test?

`ninja benchmark_lifetime_safety_analysis`

Fixes #166143

Author: usx95

clang/test/Analysis/LifetimeSafety/CMakeLists.txt

@@ -15,14 +15,21 @@ set(LIFETIME_BENCHMARK_REQUIREMENTS
 set(LIFETIME_BENCHMARK_OUTPUT_DIR
   "${CMAKE_CURRENT_BINARY_DIR}/benchmark_results")
 
+if(WIN32)
+  set(LIFETIME_BENCHMARK_VENV_PYTHON_EXECUTABLE
+    "${LIFETIME_BENCHMARK_VENV_DIR}/Scripts/python")
+else()
+  set(LIFETIME_BENCHMARK_VENV_PYTHON_EXECUTABLE
+    "${LIFETIME_BENCHMARK_VENV_DIR}/bin/python")
+endif()
 
 if(EXISTS ${LIFETIME_BENCHMARK_SCRIPT} AND EXISTS ${LIFETIME_BENCHMARK_REQUIREMENTS})
 
   # Set up the virtual environment and install packages
   add_custom_command(
     OUTPUT ${LIFETIME_BENCHMARK_VENV_DIR}/pyvenv.cfg
     COMMAND ${Python3_EXECUTABLE} -m venv ${LIFETIME_BENCHMARK_VENV_DIR}
-    COMMAND ${LIFETIME_BENCHMARK_VENV_DIR}/bin/python -m pip install -r ${LIFETIME_BENCHMARK_REQUIREMENTS}
+    COMMAND ${LIFETIME_BENCHMARK_VENV_PYTHON_EXECUTABLE} -m pip install -r ${LIFETIME_BENCHMARK_REQUIREMENTS}
     DEPENDS ${LIFETIME_BENCHMARK_REQUIREMENTS}
     COMMENT "Creating Python virtual environment and installing dependencies for benchmark..."
   )
@@ -32,7 +39,7 @@ if(EXISTS ${LIFETIME_BENCHMARK_SCRIPT} AND EXISTS ${LIFETIME_BENCHMARK_REQUIREME
 
   # Main benchmark target
   add_custom_target(benchmark_lifetime_safety_analysis
-    COMMAND ${LIFETIME_BENCHMARK_VENV_DIR}/bin/python ${LIFETIME_BENCHMARK_SCRIPT}
+    COMMAND ${LIFETIME_BENCHMARK_VENV_PYTHON_EXECUTABLE} ${LIFETIME_BENCHMARK_SCRIPT}
             --clang-binary ${LLVM_BINARY_DIR}/bin/clang
             --output-dir ${LIFETIME_BENCHMARK_OUTPUT_DIR}