fix: skip mf tests for new code splitting

[JSerFeng]

Summary

Skip MF config test case for parallel code splitting, as it fails for unknown reason and I can't repro in my local dev environment, I will enable this test case once I figure this out

Checklist

• Tests updated (or not required).
• Documentation updated (or not required).

[netlify]

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[codspeed-hq]

CodSpeed Performance Report

Merging #9047 will not alter performance

_{Comparing fix/new-code-splitting-case (b9b8e5b) with main (58a6af6)}

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Summary

✅ 3 untouched benchmarks