* Remove POST config for Grafana Alertmanager
* Delete auth + test for removed path
* Alerting: Remove check for `alertingApiServer` toggle in UI (#103805)
* Remove check for alertingApiServer in UI
* Update tests to no longer care about alertingApiServer
* Add contact points handlers now that we use alertingApiServer all the time
* Fix test broken from removing camelCase for UIDs
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Co-authored-by: Tom Ratcliffe <tom.ratcliffe@grafana.com>