Alerting docs: specify using multiple contact point integrations in the UI and HTTP API (#95890)
* Sort list of contact points on the sidebar
* Update `Configure contact points` to clarify contact point integrations
* Alerting HTTP API: fix `EmbeddedContactPoint` properties table
* HTTP Alerting API: clarify how `ContactPoint.name` groups contact points
* Update docs/sources/alerting/configure-notifications/manage-contact-points/_index.md
Co-authored-by: brendamuir <100768211+brendamuir@users.noreply.github.com>
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Co-authored-by: brendamuir <100768211+brendamuir@users.noreply.github.com>
(cherry picked from commit 290612e366)
Co-authored-by: Pepe Cano <825430+ppcano@users.noreply.github.com>