Arm backend: QAT example, save input arrays

[gggekov]

Save the input npy arrays in order to feed the same input when testing on device.

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

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❌ 1 New Failure, 34 Pending, 1 Unrelated Failure

As of commit c27489b with merge base e265ea6 ():

NEW FAILURE - The following job has failed:

• pull / test-arduino-library / run / arduino-library (gh)
  RuntimeError: Command docker exec -t 78f22cd7faf0aaef0316decd204025e3f9b8584a08e51bff713ef193f9c952a7 /exec failed with exit code 1

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

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

• Apple / build-demo-ios / macos-job (gh) (trunk failure)
  RuntimeError: Command bash /Users/runner/work/_temp/exec_script failed with exit code 65

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