Docs: Remove feature control section for project tokens

What does this MR do?

Removes the documentation section showing how to disable feature flag for project access tokens

This follows the change done by #235765 (closed) which removed away the feature flag in 13.5

The section is confusing for latest version users when they try to use it to disable the feature and find no effect

Related issues

Customer ticket (internal link)

Author's checklist (required)

• Follow the Documentation Guidelines and Style Guide.
• If you have Developer permissions or higher:
  • Ensure that the product tier badge is added to doc's h1.
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When applicable:

• Update the permissions table.
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• Add/update the feature flag section.

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