The Principled BSDF tests were previously disabled when testing
with OSL as there was a noticeable difference in noise between SVM
and OSL when mixing/layering materials.
This commit enables the Principled BSDF OSL tests, but with a increased
threshold for failure so we can test for major regressions with the
Principled BSDF OSL implementation.
Pull Request: https://projects.blender.org/blender/blender/pulls/133530
Alaska
d2930e6285