Add performance improvements for 12.4

Engineer(s): @engineers | Product Marketing: @PMM | Tech Writer: @techwriter

Content checklist

• Description is informative and focuses on the problem we're solving and the value we're delivering
• Ensure all text is consistently hard wrapped at a suitable column boundary
• Check documentation link points to the latest docs (documentation_link)
• Check that documentation is updated and easy to understand
• Check that all links to about.gitlab.com content are relative URLs
• Run the content through an automated spelling and grammar check
• Validate all links are functional

Review

When the above is complete and the content is ready for review, it should be reviewed by Product Marketing and Tech Writing:

• Tech writing

References

• Issue:
• Release post (optional): !31421 (merged)