Upgrade ARG API version (#35464) (#35492)

(cherry picked from commit 05f3985108)

Co-authored-by: shuotli <63325084+shuotli@users.noreply.github.com>

pkg/tsdb/azuremonitor/azure-resource-graph-datasource.go

@@ -42,7 +42,7 @@ type AzureResourceGraphQuery struct {
 	InterpolatedQuery string
 }
 
-const argAPIVersion = "2018-09-01-preview"
+const argAPIVersion = "2021-03-01"
 const argQueryProviderName = "/providers/Microsoft.ResourceGraph/resources"
 
 // executeTimeSeriesQuery does the following:
@@ -132,6 +132,7 @@ func (e *AzureResourceGraphDatasource) executeQuery(ctx context.Context, query *
 	reqBody, err := json.Marshal(map[string]interface{}{
 		"subscriptions": query.Model.Get("subscriptions").MustStringArray(),
 		"query":         query.InterpolatedQuery,
+		"options":       map[string]string{"resultFormat": "table"},
 	})
 
 	if err != nil {