Flickering artifacts are rendered when using Sky Atmosphere Component with Vulkan

Rendering the SkyAtmopshere component using Vulkan with and without Vulkan (SM5) enabled causes artifacts to appear on screen on Windows and Linux. 

This was reported and tested in 4.25.1 (CL-13594126) and reproduced in 4.24.3 (CL-11590370).

1. Open the UE4 Editor and create a new project
2. Go to Project Settings -> Windows -> Targeted RHIs -> enable "Vulkan (SM5)" and set "Default RHI" to Vuklan
3. Restart the Editor
4. # Delete Atmospheric Fog and the Sky Sphere from the Level
5. Add an Empty Actor to the scene
6. Attach a SkyAtmosphereComponent to the new Actor
7. Move around the Viewport

Results: Flickering artifacts when using the Vulkan RHI

Expected: There are no artifacts as D3D11 does not exhibit this issue