feat: add PDF export of docs to the CI/CD pipeline

Summary

• feat: add PDF export of docs to the CI/CD pipeline

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• Close #357
• Cherry-pick to: 24.6 / 24.5 / 24.4 / 24.3 / 24.2
• Staging:
  • https://docs.binary.picodata.io/picodata/asabirov_pdf_export_of_docs
  • ../picodata_docs.html
  • ../picodata_docs.pdf
• See also feat: export docs to pdf (!391 - closed)