fix: sidenav follow book order defined in metadata sheet

[icaraps]

Fix #104

Test URLs:

• Before: https://main--prisma-cloud-docs-website--hlxsites.hlx.page/prisma/prisma-cloud/en/compute/public-sector
• After: https://book-order--prisma-cloud-docs-website--hlxsites.hlx.page/prisma/prisma-cloud/en/compute/public-sector

[aem-code-sync[bot]]

Hello, I'm Franklin Bot and I will run some test suites that validate the page speed. In case there are problems, just click the checkbox below to rerun the respective action.

• [ ] Re-run PSI Checks

[aem-code-sync[bot]]

Page	Scores	Audits	Google
/prisma/prisma-cloud/en/compute/public-sector

[aem-code-sync[bot]]

Page	Scores	Audits	Google
/prisma/prisma-cloud/en/compute/public-sector