[iOS] Fix Unintended Dimming View Animation in NewPostEditViewController

[TakayaShirai]

Summary

The dimming view animation in NewPostEditViewController is not functioning as expected. Please investigate and fix the issue to ensure the animation works properly.

Deadline

Will decide later.

References

• Wrong Animation

https://github.com/user-attachments/assets/0b8eb9af-da5c-4821-a3d4-b122e6f80a55

• Proper Animation

https://github.com/user-attachments/assets/5c0ca72b-1628-4f22-99b9-3c85ffd0bf3e

Notes

None