OKR: Admin Area - User and IP Rate Limits- UI text

What does this MR do and why?

Update the UI text of the Admin Area > Network > User and IP Rate Limits Admin Area settings (Easy GDK link: http://localhost:3000/admin/application_settings/network):

• Adds docs link, using the same style as the other sections in the network settings page.
• Moves the repeated Helps reduce request volume... line to a single line at the top of the section, as it applies to all the rate limits universally. Placed "below the fold", so it's only visible after expanding the section.
• Change max to maximum, and other tiny copy edits.
• Adds help text to last text box.
• Removes the headers for the checkboxes, as all they were doing was repeating the name of the checkbox. This makes the page much easier to scan.
• Copy edits the docs to match:
  • Updates the docs to match the UI text.
  • Removes a screenshot that we don't need anymore.
  • Creates a a proper CTRT task for updating each setting, and adds the defaults too.

Resolves #330220 (closed)

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Related to #330220 (closed)