Fix storybook build command for v10 compatibility

[Copilot]

What are you trying to accomplish?

The "Deploy preview / Build" workflow fails with error: too many arguments for 'build'. Expected 0 arguments but got 1.

Storybook v10 changed the build command to not accept positional arguments. The build script was passing public/static as a positional arg after -o public/storybook, which is invalid syntax.

What approach did you choose and why?

Removed the public/static positional argument from docs/script/build-storybook:

-npx storybook build -o public/storybook public/static
+npx storybook build -o public/storybook

Static files are already copied via staticDirs: ['../stories/static'] in .storybook/main.js - the extra argument was redundant and now breaks with v10.

What should reviewers focus on?

Verify the workflow passes and static files are served correctly in the deployed preview.

Can these changes ship as is?

• Yes, this PR does not depend on additional changes. 🚢

Original prompt

Fix the failing GitHub Actions workflow Deploy preview / Build
Analyze the workflow logs, identify the root cause of the failure, and implement a fix.
Job ID: 61310416475
Job URL: https://github.com/primer/css/actions/runs/21298595492/job/61310416475

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[changeset-bot]

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Latest commit: d8ca91e

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