Fix test-coreml-delegate

[guangy10]

This job has been broken for a while.

The following build commands failed:
	Ld /Users/runner/work/executorch/executorch/pytorch/executorch/backends/apple/coreml/xcode-build/Debug/executorchcoreml_tests.xctest/Contents/MacOS/executorchcoreml_tests normal (in target 'executorchcoreml_tests' from project 'executorchcoreml')
(1 failure)
ExecuTorch: Failed to run CoreML tests.
ERROR conda.cli.main_run:execute(47): `conda run bash backends/apple/coreml/scripts/build_all.sh` failed. (See above for error)
    main()
  File "/Users/runner/work/executorch/executorch/test-infra/.github/scripts/run_with_env_secrets.py", line 60, in main
    run_cmd_or_die(f"bash { os.environ.get('RUNNER_TEMP', '') }/exec_script")
  File "/Users/runner/work/executorch/executorch/test-infra/.github/scripts/run_with_env_secrets.py", line 38, in run_cmd_or_die
    raise RuntimeError(f"Command {cmd} failed with exit code {exit_code}")
RuntimeError: Command bash /Users/runner/work/_temp/exec_script failed with exit code 1

See full stack trace here: https://github.com/pytorch/executorch/actions/runs/7705685481/job/21000020592

[guangy10]

@shoumikhin Do you have any idea about the issue? Who is the right PoC from Apple could take a look?

[shoumikhin]

@guangy10 I believe PR #1747 is to fix that.