fix：租户禁用后，还展示了“租户切换权限”的按钮

(cherry picked from commit d72946100abc63abdb9dab493a8e7b9a1c2d6af2)

src/layout/components/ToolHeader.vue

@@ -44,7 +44,9 @@ const locale = computed(() => appStore.getLocale)
 const message = computed(() => appStore.getMessage)
 
 // 租户切换权限
-const hasTenantVisitPermission = computed(() => checkPermi(['system:tenant:visit']))
+const hasTenantVisitPermission = computed(
+  () => import.meta.env.VITE_APP_TENANT_ENABLE === 'true' && checkPermi(['system:tenant:visit'])
+)
 
 export default defineComponent({
   name: 'ToolHeader',