Arm backend: Consolidate CI testing

[zingo]

Testing is done via test_arm_backed.sh instead of different scripts. OOBT tests in CI is part of the test matrix instead of separate job descriptions doing the same thing.
GitHub job names all start with test-arm-backend making it easier know what jobs belongs to and to filter in the HUD.

Test plan

Github testing

cc @digantdesai @freddan80 @per @oscarandersson8218 @mansnils @Sebastian-Larsson @robell @rascani

[pytorch-bot]

🔗 Helpful Links

🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/19696

• 📄 Preview Python docs built from this PR

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

❗ 1 Active SEVs

There are 1 currently active SEVs. If your PR is affected, please view them below:

• Run pull request jobs on OSDC runners in shadow mode

❌ 1 Cancelled Job, 1 Unrelated Failure, 1 Unclassified Failure

As of commit e924c16 with merge base 7724fd7 ():

UNCLASSIFIED FAILURE - DrCI could not classify the following job because the workflow did not run on the merge base. The failure may be pre-existing on trunk or introduced by this PR:

• .github/workflows/pull.yml (gh) (this job did not run on the merge base, so DrCI cannot tell whether the failure is pre-existing)

CANCELLED JOB - The following job was cancelled. Please retry:

• trunk / test-models-macos-cpu (llama, portable) / macos-job (gh)
  ##[error]The operation was canceled.

BROKEN TRUNK - The following job failed but were present on the merge base:

👉 Rebase onto the `viable/strict` branch to avoid these failures

• trunk / unittest-release / macos / macos-job (gh) (trunk failure)
  ##[error]The operation was canceled.

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

[Copilot]

Pull request overview

This PR consolidates Arm backend CI coverage by routing out-of-the-box (OOTB) notebook/e2e checks through backends/arm/test/test_arm_backend.sh, simplifying the workflow matrix and standardizing job naming.

Changes:

• Add OOTB test entrypoints to test_arm_backend.sh that delegate to test_arm_ootb.sh.
• Add a dedicated requirements file for OOTB notebook execution (notebook, nbconvert) and install it on-demand in the OOTB script.
• Update CI workflows to include OOTB tests in the Arm backend test matrices and remove the standalone OOTB CI job; rename the PR workflow Arm job.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
backends/arm/test/test_arm_ootb.sh	Adds repo-root/requirements discovery and on-demand install for notebook execution deps.
backends/arm/test/test_arm_backend.sh	Introduces new test_* entrypoints to run OOTB suites via test_arm_ootb.sh.
backends/arm/requirements-arm-ootb-test.txt	New requirements list for OOTB notebook conversion/execution.
backends/arm/README.md	Documents the newly added OOTB test entrypoints.
.github/workflows/trunk.yml	Moves OOTB coverage into the existing Arm backend test matrices; removes standalone OOTB job.
.github/workflows/pull.yml	Renames the Arm backend “no driver” job (but currently introduces a YAML syntax issue).

Comments suppressed due to low confidence (1)

backends/arm/test/test_arm_ootb.sh:40

• install_ootb_test_requirements falls back to pip install ... if the imports fail. Using bare pip can install into a different interpreter than python3 (especially in conda), which can still leave python3/jupyter missing the modules. Prefer python3 -m pip install -r "${ootb_requirements}" (and ideally check that jupyter nbconvert is available after install).

install_ootb_test_requirements() {
    python3 - <<'PY' || pip install -r "${ootb_requirements}"
import notebook  # noqa: F401
import nbconvert  # noqa: F401
PY
}

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.