fix[Breadcrumb]: fixed eslint error

src/components/Breadcrumb/index.vue

 <template>
   <el-breadcrumb class="app-breadcrumb" separator="/">
     <transition-group name="breadcrumb">
-      <el-breadcrumb-item v-for="(item,index) in levelList" v-if="item.meta.title&&item.meta.breadcrumb!==false" :key="item.path">
+      <el-breadcrumb-item v-for="(item,index) in levelList" :key="item.path">
         <span v-if="item.redirect==='noredirect'||index==levelList.length-1" class="no-redirect">{{ item.meta.title }}</span>
         <a v-else @click.prevent="handleLink(item)">{{ item.meta.title }}</a>
       </el-breadcrumb-item>
@@ -28,16 +28,14 @@ export default {
   },
   methods: {
     getBreadcrumb() {
-      let matched = this.$route.matched.filter(item => {
-        if (item.name) {
-          return true
-        }
-      })
+      let matched = this.$route.matched.filter(item => item.name)
+
       const first = matched[0]
       if (first && first.name !== 'dashboard') {
         matched = [{ path: '/dashboard', meta: { title: 'Dashboard' }}].concat(matched)
       }
-      this.levelList = matched
+
+      this.levelList = matched.filter(item => item.meta && item.meta.title && item.meta.breadcrumb !== false)
     },
     pathCompile(path) {
       // To solve this problem https://github.com/PanJiaChen/vue-element-admin/issues/561