[Release-3.14][E2E Test] Prevent the bad IndexError when build image fails

[hehe7318]

Description of changes

Prevent the bad IndexError when build image fails

When build image fails, the image_list is empty but the code directly accesses image_list[0], causing IndexError that masks the real error. Add safety check to only access list elements when list is not empty.

Checklist

• Make sure you are pointing to the right branch.
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• Make sure to have added unit tests or integration tests to cover the new/modified code.
• Check if documentation is impacted by this change.

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