fix: remove unused events from UserStorageController (#5324)

## Explanation

This PR removes unused event types from `UserStorageController`

## References

## Changelog

### `@metamask/profile-sync-controller`

- **REMOVED**: removed unused events from `UserStorageController`

## Checklist

- [x] I've updated the test suite for new or updated code as appropriate
- [x] I've updated documentation (JSDoc, Markdown, etc.) for new or
updated code as appropriate
- [x] I've highlighted breaking changes using the "BREAKING" category
above as appropriate
- [x] I've prepared draft pull requests for clients and consumer
packages to resolve any breaking changes

packages/profile-sync-controller/src/controllers/user-storage/UserStorageController.ts

@@ -256,23 +256,11 @@ export type UserStorageControllerStateChangeEvent = ControllerStateChangeEvent<
   typeof controllerName,
   UserStorageControllerState
 >;
-export type UserStorageControllerAccountSyncingInProgress = {
-  type: `${typeof controllerName}:accountSyncingInProgress`;
-  payload: [boolean];
-};
-export type UserStorageControllerAccountSyncingComplete = {
-  type: `${typeof controllerName}:accountSyncingComplete`;
-  payload: [boolean];
-};
-export type Events =
-  | UserStorageControllerStateChangeEvent
-  | UserStorageControllerAccountSyncingInProgress
-  | UserStorageControllerAccountSyncingComplete;
+
+export type Events = UserStorageControllerStateChangeEvent;
 
 export type AllowedEvents =
   | UserStorageControllerStateChangeEvent
-  | UserStorageControllerAccountSyncingInProgress
-  | UserStorageControllerAccountSyncingComplete
   | KeyringControllerLockEvent
   | KeyringControllerUnlockEvent
   // Account Syncing Events