NEZ-2078 fix：新建System修改不同的Display点击预览，偶尔会出现图表超出预览框现象

nezha-fronted/src/components/common/rightBox/chart/chartRightBox.vue

@@ -497,17 +497,19 @@ export default {
       }
     },
     preview (show) {
+      this.previewShow = show
       if (show) {
+        this.$nextTick(() => {
           const start = new Date().setHours(new Date().getHours() - 1)
           const end = new Date()
           this.timeRange = [bus.computeTimezoneTime(start), bus.computeTimezoneTime(end)]
+          setTimeout(() => {
             this.prevChart = lodash.cloneDeep(this.editChart)
             this.prevChart.loaded = true
             this.prevChart.param.showHeader = true
-      }
-      this.$nextTick(() => {
-        this.previewShow = show
           })
+        })
+      }
     }
   },
   created () {