Updates the Advanced settings section of the Gating Group Collections page to cover the publisher gating changes that shipped for Enterprise Plus orgs.

Previously the docs only described blocked countries auto-rejecting access requests on gated repos. The settings now also include:

• Blocked regions, for territories that aren't distinct countries and so can't be picked from the country list.
• An Enforcement choice between "Gated repositories" (auto-reject access requests, the previous behavior) and "All repositories", which also denies downloads on every repo including public ones, shows a "not available in your region" notice, and disables the dataset viewer for blocked visitors.

Also notes that org members aren't exempt from enforcement.

Notes for reviewers

• This content lives on the Gating Group Collections page because that's where the existing blocked-countries paragraph was. The "All repositories" scope applies org-wide and isn't specific to gating group collections, so it may deserve its own page or a home under the Enterprise docs. Happy to move it if you'd prefer.
• The Advanced Gating tab name is unchanged, though it now covers more than gating.