fix: do not use datasourcePromises for 5.x before 5.4

dist/status_heatmap_ctrl.js

@@ -208,9 +208,14 @@ System.register(['app/plugins/sdk', 'lodash', 'app/core/core', 'app/core/utils/k
              * (but not wait for completion). This resolves
              * issue 11806.
              */
+            // 5.x before 5.4 doesn't have dataPromises
+            if ("undefined" !== typeof _this.annotationsSrv.datasourcePromises) {
               return _this.annotationsSrv.datasourcePromises.then(function (r) {
                 return _get(StatusHeatmapCtrl.prototype.__proto__ || Object.getPrototypeOf(StatusHeatmapCtrl.prototype), 'issueQueries', _this).call(_this, datasource);
               });
+            } else {
+              return _get(StatusHeatmapCtrl.prototype.__proto__ || Object.getPrototypeOf(StatusHeatmapCtrl.prototype), 'issueQueries', _this).call(_this, datasource);
+            }
           };
 
           _this.onDataReceived = function (dataList) {

src/status_heatmap_ctrl.js

@@ -206,9 +206,14 @@ export class StatusHeatmapCtrl extends MetricsPanelCtrl {
      * (but not wait for completion). This resolves
      * issue 11806.
      */
+    // 5.x before 5.4 doesn't have dataPromises
+    if ("undefined" !== typeof(this.annotationsSrv.datasourcePromises)) {
       return this.annotationsSrv.datasourcePromises.then(r => {
         return super.issueQueries(datasource);
       });
+    } else {
+      return super.issueQueries(datasource);
+    }
   }