Add sectionTitle components to about:styles

[luixxiul]

Test plan

#8237 (comment)

1. Open about:styles
2. Click "commonForm" on TOC
3. Make sure the template of the commonForm is displayed
4. Click "Go back to top"
5. Click "sectionTitle" on TOC
6. Make sure section title components are displayed

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Describe the issue you encountered:
Add sectionTitle components to about:styles.

• Extra QA steps:
  1.
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• Screenshot if needed:

• Any related issues: Create sectionTitle.js #8237