perf: change attachment list layout to list mode (#827)

#### What type of PR is this?

/kind improvement

#### What this PR does / why we need it:

目前暂时没有缩略图功能，上传大量的大型图片很容易造成浏览器崩溃，故我们临时将附件管理的默认视图模式改为列表模式。

#### Which issue(s) this PR fixes:

Fixes https://github.com/halo-dev/halo/issues/3167

#### Screenshots:

<img width="1692" alt="image" src="https://user-images.githubusercontent.com/21301288/212832865-f1f22ce2-860f-497a-b091-b4552458bd77.png">


#### Special notes for your reviewer:

#### Does this PR introduce a user-facing change?


```release-note
Console 附件管理的默认视图模式改为列表模式。
```

src/modules/contents/attachments/AttachmentList.vue

@@ -241,7 +241,7 @@ const viewTypes = [
   },
 ];
 
-const viewType = useRouteQuery<string>("view", "grid");
+const viewType = useRouteQuery<string>("view", "list");
 
 // Route query action
 const routeQueryAction = useRouteQuery<string | undefined>("action");