Help view does not respect notch after rotation

[twstokes]

Describe the bug
When the Help view (which is a full screen sheet) is rotated from portrait to landscape and back to portrait, its top does not return to its original location under the device's notch. Instead, the view's top equals the top of the device's screen.

To Reproduce
Steps to reproduce the behavior:

1. In the portrait orientation, open the block editor in WPiOS by creating a new post.
2. Tap the three dots at the top right.
3. Tap "Help".
4. Observe that the top of the view is under the notch.
5. Rotate the device into landscape.
6. Rotate the device back to portrait.
7. Observe that the top of the view is at the top of the device's screen.
8. Observe that the "Close" button at the top left may not be usable.

Expected behavior
The top of the view stays under the notch.

Screenshots

Smartphone (please complete the following information):

• Device: iPhone 12
• OS: iOS 14.5, iOS 15
• Version 18.1

Additional context
This was also tested on an iPhone 8 (a notchless device) and it didn't seem to be affected.