hillshade rendering artifacts, regression in iOS 6.6.0

[JesseCrocker]

Describe the bug
The iOS 6.6.0 release seems to have introduced a bug related to hillshade rendering, while the map is moving there are sometimes lots of flashing, and line artifacts. But once all data is loaded, it renders correctly. There are several examples of this happening in the attached video. This was not happening in 6.5.4

Expected behavior
A clear and concise description of what you expected to happen.

Screenshots

Simulator.Screen.Recording.-.iPhone.15.-.2024-09-16.at.12.31.39.mp4

Platform information (please complete the following information):

• OS: iOS 17.x
• Platform iOS
• Version 6.6.0

[louwers]

Also happens with MapTiler Outdoors.

[louwers]

I did a git bisect, seems like #2629 started to introduce issues with hillshading. @TimSylvester could you have a look at this?