*Steps to reproduce:*
# Download and open the attached project (Bug-HDRP-CloudLayer.zip)
# Select the Sky and Fog Volume
# In the Cloud Layer, check one of the opacity channels (Opacity R, B, G, or A)
# Lower the opacity value
# Switch to the Game view (or look directly overhead)

*Expected result:*
* Procedural skybox looks clean, regardless of the opacity value used

*Actual result:*
* A bright, dot-like artifact is visible directly overhead, where the cloud layer converges (see attachment CloudOpacity-0.1.png)

*Notes:*
* Reproducible in Unity 2021.3+
* Reproduces in HDRP only
* Only reproduces when tweaking individual Opacity channels; does not reproduce when tweaking the global Opacity parameter