Put an alert on “autoendpoint bridge notifications by platform”

[data-sync-user]

From the most recent GCM incident, we learned that it would be a good idea to have an alert triggered if any kind of traffic drops precipitously (or to zero) on “autoendpoint bridge notifications by platform” (aka +https://earthangel-b40313e5.influxcloud.net/d/do4mmwcVz/autopush-gcp?orgId=1&from=now-7d&to=now&refresh=1m&viewPanel=20+)

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