Support docs images in regression tests

[Janpot]

serve can't get out of the build folder, but we could create a symlink in the build folder to the docs public/static folder.

images seem to be deliberately blocked out of performance considerations. I'm not seeing a measurable difference in runtimeof the regressions test job.

[mui-bot]

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[Janpot]

Works, but benefits not 100% clear.