[CI] Skip ONNX Upscale tests

[DN6]

What does this PR do?

External repo used in ONNX Upscale Pipeline test has a potential vulnerability. To be safe we'll skip these tests for now until we resolve the repo issue.

Note a similar issue is present in the hf-internal-testing/tiny-random-OnnxStableDiffusionPipeline repo as well. But we control merges there. So need not skip for now.

#11762

Fixes # (issue)

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