Remove scoped visibility from the docs engine

[ptgott]

Closes gravitational/teleport#19471
Closes gravitational/teleport#30381
Closes #343
Closes #162
Closes #155
Closes #118
Closes #116
Closes #88

Users tend not to notice the scope switcher. When they do, the
component's behavior is not intuitive. This change removes the scope
switcher from the docs, replacing it with a non-interactive list of
supported Teleport editions.

The change preserves the existing styling of the scope switcher as much
as possible. Aside from an "Available for" label next to the edition
list, the change should go unnoticed for users who do not interact with
the scope switcher.

This change also adjust some docs behavior that relied on the scope
switcher:

• The DocsContext no longer includes the current scope: Components
  no longer refer to the DocsContext to determine the currently
  selected scope and adjust their visibility.

  "Box" components like the Details, Notice, and Admonition
  component can currently hide themselves if the selected scope does not
  match the value of the scope prop. This change shows these boxes at
  all times, but keeps the scope and scopeOnly props for backwards
  compatability (the props are no-op).

  The Tabs component currently uses the selected scope to select a
  TabItem with the scope property. Since we merged Switch TabItems with identical labels together #380, though,
  Tabs components can preserve most of this behavior without the scope
  switcher, as long as these components include identical labels for
  edition-related tab items. This change also retains the scope prop
  in no-op form.

• Locking the version picker if the scope is cloud or team: This
  change no longer locks the version picker, since there is no way to
  select a scope. Locking the version picker becomes an issue when
  Teleport Cloud is a major version behind the latest release. Removing
  the scope switcher doesn't completely rectify this, since the version
  of the docs for the previous version includes a warning banner. We can
  address this in a future change.

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Name	Status	Preview	Comments	Updated (UTC)
docs	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Sep 5, 2023 7:32pm

[ptgott]

Reviewer notes:

• This change includes changes I made in Remove the ScopedBlock from the docs engine #382 .
• Here's what the scope switcher looks like as of 315c611 . I don't like the spacing between the "Available for" label and the first list item, but I'm not sure what a good alternative would be. @roraback do you have any suggestions?

[avatus]

Code looks good but lets await some product approvals as well

[xinding33]

This change looks good to me for a short-term fix. Long term, as we've discussed internally, I'd rather revamp the information architecture.