Arm backend: Add infer_shapes to test infra.

[oscarandersson8218]

For tosa-flatbuffers with unresolved shapes, we need to invoke infer_shapes to resolve shapes before invoking tosa_reference_model. This change will make sure that infer_shapes is called before reference_model when shape-extension is enabled and any input has a symbolic dimension.

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

[pytorch-bot]

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• [ROCm] MI350 CI jobs will have longer queue times due to CI migration

❌ 2 New Failures, 1 Cancelled Job, 3 Unrelated Failures

As of commit 6565b98 with merge base 111e93c ():

NEW FAILURES - The following jobs have failed:

• pull / test-qnn-models-linux (mv3) / linux-job (gh)
  RuntimeError: Command docker exec -t a7bff9c985dcce281319f3fc990b7f7b4c6148ecd2ae92fa4fcc9473b5957a58 /exec failed with exit code 92
• trunk / test-qnn-model (fp32, ic3) / linux-job (gh)
  RuntimeError: Command docker exec -t cf1e991a5b8a9bd921ea5f279645dc20c071d8cc975e5e3c1ec9799b358c0d41 /exec failed with exit code 92

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

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

FLAKY - The following job failed but was likely due to flakiness present on trunk:

• pull / test-qnn-testsuite-linux / test-backend-linux (qnn, models) / linux-job (gh) (matched linux rule in flaky-rules.json)
  The runner has received a shutdown signal. This can happen when the runner service is stopped, or a manually started runner is canceled.

BROKEN TRUNK - The following jobs failed but was present on the merge base:

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

• pull / test-llama-runner-qnn-linux (fp32, qnn_16a16w, qnn) / linux-job (gh) (trunk failure)
• trunk / test-llama-runner-qnn-linux (fp32, qnn_16a16w, qnn) / linux-job (gh) (trunk failure)

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[oscarandersson8218]

Unrelated failures.