Add json header to buck needed for CoreML multifunction passed metadata parsing

[derekxu]

Summary:
Add json header to buck needed for CoreML multifunction passed metadata parsing

• Scott added for OSS only on CMake, this is also needed for buck

Differential Revision: D90783270

[pytorch-bot]

🔗 Helpful Links

🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/16634

• 📄 Preview Python docs built from this PR

Note: Links to docs will display an error until the docs builds have been completed.

❌ 3 New Failures

As of commit 66d4f22 with merge base 33974d5 ():

NEW FAILURES - The following jobs have failed:

• pull / android / run-emulator (gh)
  Timeout waiting for emulator to boot.
• pull / unittest / macos / macos-job (gh)
  backends/apple/coreml/test/test_coreml_multifunction.py::TestCoreMLMultifunction::test_multifunction_with_kv_cache
• pull / unittest-editable / macos / macos-job (gh)
  backends/apple/coreml/test/test_coreml_multifunction.py::TestCoreMLMultifunction::test_multifunction_with_kv_cache

This comment was automatically generated by Dr. CI and updates every 15 minutes.

[meta-codesync]

@derekxu has exported this pull request. If you are a Meta employee, you can view the originating Diff in D90783270.

[github-actions]

This PR needs a release notes: label

If your change should be included in the release notes (i.e. would users of this library care about this change?), please use a label starting with release notes:. This helps us keep track and include your important work in the next release notes.

To add a label, you can comment to pytorchbot, for example
@pytorchbot label "release notes: none"

For more information, see
https://github.com/pytorch/pytorch/wiki/PyTorch-AutoLabel-Bot#why-categorize-for-release-notes-and-how-does-it-work.