Alerting: Support conditional enrichments

[alexander-akhmetov]

Adding support for conditional enrichments (limited to a single level for now):

resource "grafana_apps_alertenrichment_alertenrichment_v1beta1" "enrichment" {
  metadata {
    uid = "test_enrichment"
  }

  spec {
    title       = "Conditional alert enrichment"

    step {
      conditional {
        if {
          label_matchers = [{
            type  = "="
            name  = "severity"
            value = "critical"
          }]
        }

        then {
          step {
            assign {
              annotations = {
                escalation_level = "immediate"
              }
            }
          }
          step {
            external {
              url = "https://irm.grafana.com/create-incident"
            }
          }
        }

        else {
          step {
            assign {
              annotations = {
                escalation_level = "standard"
              }
            }
          }
        }
      }
    }
  }
}

Part of github.com/grafana/alerting-enricher/issues/73

[github-actions]

In order to lower resource usage and have a faster runtime, PRs will not run Cloud tests automatically.
To do so, a Grafana Labs employee must trigger the cloud acceptance tests workflow manually.