Reversed the descriptions of accessibility levels

What does this MR do?

This MR is broken into two issues. In this MR, we will fix the descripiton 👍

• The public/internal/private descriptions were inversed.
• GitLab.com is showing "Internal" which is not allowed (may need to leverage something server-side?).

Related to: #329575 (closed) Related to: #321387 (closed)

Found by: @juliebyrne

Introduced by: !53544 (merged)

Screenshots (strongly suggested)

Before	This MR

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Conformity

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• Documentation (if required)
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• Separation of EE specific content

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