Use the Python executable that CMake discovered during configuration

Author: tomchapman

tests/run_integrated_tests.sh

@@ -7,5 +7,6 @@ export PYTHONPATH="@PROJECT_BINARY_DIR@/tools/pylib:@PROJECT_SOURCE_DIR@/tools/p
 # Pre-build the project to prevent concurrent CMake race conditions
 cmake --build "$PROJECT_ROOT"
 
-python3 -m pytest -m "not serial" --cache-clear -n auto --dist=loadgroup -q "$PROJECT_ROOT/tests/integrated" "$@"
-python3 -m pytest -m serial "$PROJECT_ROOT/tests/integrated" "$@"
+# Use the Python executable that CMake discovered during configuration
+"@Python3_EXECUTABLE@" -m pytest -m "not serial" --cache-clear -n auto --dist=loadgroup -q "$PROJECT_ROOT/tests/integrated" "$@"
+"@Python3_EXECUTABLE@" -m pytest -m serial "$PROJECT_ROOT/tests/integrated" "$@"