Fix the problem of incorrect role template for appstore (#49)

This PR fixes the incorrect rule configuration of role template of app store.

/kind bug

```release-note
修复应用管理角色失效的问题
```

src/main/resources/extensions/store-role-template.yaml

@@ -13,6 +13,6 @@ metadata:
       [ "role-template-manage-plugins", "role-template-manage-themes" ]
 rules:
   - apiGroups: [""]
-    resources: ["secret"]
+    resources: ["secrets"]
     resourceNames: ["halo-run-app-store-pat-secret"]
     verbs: ["create", "update", "get", "delete"]