Missing Assembly Ref in UnityEngine.Experimental.Rendering.Universal

@CodeSmile
Huh, apparently I cant really remove the package?
When clicking on the remove button it apparently removes it but then it locks it and the remove button is greyed out saying that the package cant be removed because another installed package depends on it. But the manifest file does not list the package anymore, the packages-lock file does list an pixel perfect entry, the depth value is just set to 1.
I pushed this change and made a build and it still failed with the same errors, so I guess it wasnt really removed, which is weird since I dont even use this package at all and afaik it’s basically one script that you attach to cameras.