fix：修改 chartBox修改时type为 singleStat expression可以添加多个的问题以及处理侧滑样式错乱的问题

nezha-fronted/src/components/page/dashboard/chartBox.vue

@@ -64,7 +64,7 @@
     height: 100vh;
     top: 0;
     left: 0;
-    /*z-index: 2100;*/
+    z-index: 1;
   }
   /deep/ .el-color-picker{
     position: absolute;
@@ -1247,6 +1247,8 @@
             this.$refs.alertParamBox.setData(data)
           })
           //this.elements=[1];
+        }else if(this.editChart.type==='singleStat'){
+          this.setIsSingleStat();
         }else{
           if((this.editChart.type==='line'||this.editChart.type==='bar'||this.editChart.type==='stackArea'||this.editChart.type==='singleStat')&&data.param){
             this.editChart.param.threshold=data.param.threshold;