Bind graph using the DOM element instead of id

Billboard must receive the graph element directly because the chart can be
rendered while it is still detached from the document.

Closes #14970

sao/src/view/graph.js

@@ -69,7 +69,6 @@
             this.xfield = xfield;
             this.yfields = yfields;
             this.el = jQuery('<div/>');
-            this.el.uniqueId();
         },
         update_data: function(group) {
             var data = {};
@@ -171,7 +170,7 @@
         _bb_config: function(data) {
             var bb_config = {};
 
-            bb_config.bindto = '#' + this.el.attr('id');
+            bb_config.bindto = this.el.get(0);
             bb_config.data = data;
             bb_config.data.type = this._chart_type;
             bb_config.data.x = 'labels';