perf: add success toast for saving plugin and theme settings (#895)

#### What type of PR is this?

/kind improvement

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

保存主题和插件设置时，添加保存成功的反馈提示。

#### Screenshots:

<img width="803" alt="image" src="https://user-images.githubusercontent.com/21301288/221805091-60f3f20c-5524-4dea-9858-6c521cb1dfbc.png">

#### Special notes for your reviewer:

None

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


```release-note
None
```

src/modules/interface/themes/ThemeSetting.vue

@@ -3,7 +3,7 @@
 import { inject, ref, watch } from "vue";
 
 // components
-import { VButton } from "@halo-dev/components";
+import { Toast, VButton } from "@halo-dev/components";
 
 // types
 import type { Ref } from "vue";
@@ -63,6 +63,8 @@ const handleSaveConfigMap = async () => {
     configMap: configMapToUpdate,
   });
 
+  Toast.success("保存成功");
+
   await handleFetchSettings();
   configMap.value = newConfigMap;
 

src/modules/interface/themes/components/preview/ThemePreviewModal.vue

@@ -21,6 +21,7 @@ import {
   IconPhone,
   IconTablet,
   IconRefreshLine,
+  Toast,
 } from "@halo-dev/components";
 import { storeToRefs } from "pinia";
 import { computed, markRaw, ref, watch } from "vue";
@@ -163,6 +164,8 @@ const handleSaveConfigMap = async () => {
     configMap: configMapToUpdate,
   });
 
+  Toast.success("保存成功");
+
   await handleFetchSettings();
   configMap.value = newConfigMap;
 

src/modules/system/plugins/PluginSetting.vue

@@ -7,7 +7,7 @@ import { useSettingFormConvert } from "@/composables/use-setting-form";
 import { apiClient } from "@/utils/api-client";
 
 // components
-import { VButton } from "@halo-dev/components";
+import { Toast, VButton } from "@halo-dev/components";
 
 // types
 import type { ConfigMap, Plugin, Setting } from "@halo-dev/api-client";
@@ -55,6 +55,8 @@ const handleSaveConfigMap = async () => {
     configMap: configMapToUpdate,
   });
 
+  Toast.success("保存成功");
+
   await handleFetchSettings();
   configMap.value = newConfigMap;
   saving.value = false;