[DRAFT] Fleet UI: Add certificates (SCEP/NDES) section to integrations settings

[RachelElysia]

Issue

Cerra #22125

Description

• UI for Certificates section

Other

• Lots of CSS / code cleanup by creating a reusable <SectionCard/> component and styling

Screenrecording

TODO

Checklist for submitter

If some of the following don't apply, delete the relevant line.

• Changes file added for user-visible changes in changes/, orbit/changes/ or ee/fleetd-chrome/changes.
  See Changes files for more information.
• Input data is properly validated, SELECT * is avoided, SQL injection is prevented (using placeholders for values in statements)
• Added support on fleet's osquery simulator cmd/osquery-perf for new osquery data ingestion features.
• Added/updated tests
• If paths of existing endpoints are modified without backwards compatibility, checked the frontend/CLI for any necessary changes
• If database migrations are included, checked table schema to confirm autoupdate
• For database migrations:
  • Checked schema for all modified table for columns that will auto-update timestamps during migration.
  • Confirmed that updating the timestamps is acceptable, and will not cause unwanted side effects.
  • Ensured the correct collation is explicitly set for character columns (COLLATE utf8mb4_unicode_ci).
• Manual QA for all new/changed functionality
• For Orbit and Fleet Desktop changes:
  • Orbit runs on macOS, Linux and Windows. Check if the orbit feature/bugfix should only apply to one platform (runtime.GOOS).
  • Manual QA must be performed in the three main OSs, macOS, Windows and Linux.
  • Auto-update manual QA, from released version of component to new version (see tools/tuf/test).