sync repo source code with rel-1.15.0 and update yml files into two stages

objectivec/test/testdata/gen_models.sh

@@ -0,0 +1,12 @@
+#!/bin/bash
+
+set -e
+
+# Get directory this script is in
+DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+
+cd ${DIR}
+
+python3 ./single_add_gen.py
+
+ORT_CONVERT_ONNX_MODELS_TO_ORT_OPTIMIZATION_LEVEL=basic python3 -m onnxruntime.tools.convert_onnx_models_to_ort --optimization_style=Fixed .