Fix alignment of wiki sitemap and templates pages

What does this MR do and why?

Fixes alignment of wiki sitemap and templates pages (sidebar should remain unaffected)

• Remove borders in sitemap to help tighten up spacing and get a better overall picture of the page hierarchy
• Remove last edited timestamps
  • It was too difficult to see which timestamp went with which page without the borders, and I'm not sure it's necessary information on this specific page (which also makes me wonder if we should remove the file type badge)
• Tweak spacing of indentation on templates page
• Move carets next to page titles on templates and sitemap pages

Open questions

• Should we remove the file type badges on both templates and sitemap pages? Removed
• Should we remove last edited on templates page too? Removed

Screenshots or screen recordings

	Before	After
Sitemap
Templates
Pages sidebar

How to set up and validate locally

• Go to wiki sitemap (eg http://127.0.0.1:3000/flightjs/Flight/-/wikis/pages)
• Go to templates (eg http://127.0.0.1:3000/flightjs/Flight/-/wikis/templates)
• Go to wiki page to see sidebar (eg http://127.0.0.1:3000/flightjs/Flight/-/wikis/_sidebarr)

Links

• ✂️ UX Paper Cuts 17.1 → Improve Wiki Experience (#452225 - closed)