ui: Send item name down to Stats to call endpoint (#9358)

* Refactor Stats and Series components

* Remove unused variable from being passed down to Stats

* Add item name to be passed down to Stats

ui/packages/consul-ui/app/components/topology-metrics/index.hbs

@@ -30,6 +30,7 @@
         @dc={{item.Datacenter}}
         @endpoint='downstream-summary-for-service'
         @service={{@service.Service.Service}}
+        @item={{item.Name}}
         @noMetricsReason={{this.noMetricsReason}}
       />
     {{/if}}
@@ -96,6 +97,7 @@
           @dc={{item.Datacenter}}
           @endpoint='upstream-summary-for-service'
           @service={{@service.Service.Service}}
+          @item={{item.Name}}
           @noMetricsReason={{this.noMetricsReason}}
         />
       {{/if}}