[PyT] Install pytest in onnx L1 test as Pyt container no longer packages it (NVIDIA#2781)

Install pytest in onnx L1 test as Pyt container no longer packages it

Signed-off-by: Kshitij Janardan Lakhani <klakhani@nvidia.com>

Author: KshitijLakhani

qa/L1_pytorch_onnx_unittest/test.sh

@@ -2,9 +2,15 @@
 #
 # See LICENSE for license information.
 
+function error_exit() {
+    echo "Error: $1"
+    exit 1
+}
+
 : ${TE_PATH:=/opt/transformerengine}
 : ${XML_LOG_DIR:=/logs}
 mkdir -p "$XML_LOG_DIR"
 
+pip3 install pytest==8.2.1 || error_exit "Failed to install pytest"
 # NVTE_UnfusedDPA_Emulate_FP8=1 enables FP8 attention emulation when no native backend is available
 NVTE_UnfusedDPA_Emulate_FP8=1 python3 -m pytest --tb=auto --junitxml=$XML_LOG_DIR/test_onnx_export.xml $TE_PATH/tests/pytorch/test_onnx_export.py