[CI] GLM-Image testcases

[chickeyton]

PLEASE FILL IN THE PR DESCRIPTION HERE ENSURING ALL CHECKLIST ITEMS (AT THE BOTTOM) HAVE BEEN CONSIDERED.

Purpose

1. An answer to [RFC]: L4 e2e tests of diffusion models and diffusion features (continuous maintanance)

Test i2i 1024x1024 image on single card, other features and image sizes will be tested in the later PR after GLM-Image bug #2222 got fixed

2. Fixed the bug of GLM-Image requires "image" mm data field, but AI server passed "img2img" mm data field

Test Plan

cd tests/e2e/online_serving
pytest -s test_glm_image_expansion.py

Test Result

all test passed without failed

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Essential Elements of an Effective PR Description Checklist

• The purpose of the PR, such as "Fix some issue (link existing issues this PR will resolve)".
• The test plan. Please provide the test scripts & test commands. Please state the reasons if your codes don't require additional test scripts. For test file guidelines, please check the test style doc
• The test results. Please paste the results comparison before and after, or the e2e results.
• (Optional) The necessary documentation update, such as updating supported_models.md and examples for a new model. Please run mkdocs serve to sync the documentation editions to ./docs.
• (Optional) Release notes update. If your change is user-facing, please update the release notes draft.

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