Arm backend: Add index_copy test

[tom-arm]

• Add index_copy tests, to check the op fully delegates (except for U55)
• Add tests for inplace and out-of-place versions

Change-Id: Ia1df838cee75eb4cc3061e6b4d58fba0a6bb910d

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

[pytorch-bot]

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❌ 1 Cancelled Job, 3 Unrelated Failures

As of commit 0da5d37 with merge base b1373e8 ():

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

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

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

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

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

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[zingo]

OK to merge just make sure Arm Test is tested green.
For example I see
backends/arm/test/misc/test_conv_relu_residual_add.py::test_conv_relu_residual_add_u55_INT[per_channel_quantization=false]
But maybe it just need re-run as it seems unrelated.

[tom-arm]

Failures are unrelated