修复tabs关闭最后一个tab后，再次打开会保留最后一个tab bug

src/views/main-content.vue

      },
      // tabs, 删除tab
      removeTabHandle (tabName) {
        var newTabs = this.mainTabs.filter(item => item.name !== tabName)
        if (newTabs.length >= 1) {
        this.mainTabs = this.mainTabs.filter(item => item.name !== tabName)
        if (this.mainTabs.length >= 1) {
          // 当前选中tab被删除
          if (tabName === this.mainTabsActiveName) {
            this.$router.push({ name: newTabs[newTabs.length - 1].name }, () => {
            this.$router.push({ name: this.mainTabs[this.mainTabs.length - 1].name }, () => {
              this.mainTabsActiveName = this.$route.name
            })
          }
          this.mainTabs = newTabs
        } else {
          this.menuActiveName = ''
          this.$router.push({ name: 'home' })