Hair Material's Tangents input has no effect in PathTracing

Expectation: Tangent should work on Hair Material

Open the project(5.5) and the material used on the hairs

Tweaking Tangent parameter has no effect on Hair when using PT; It has big impact on Deferred rendering though

Here the test result for your references:
Hair shader on Groom effective inputs * DF：BaseColor, Specular, Roughness，Tangent，Backlit

• PT： BaseColor， Scatter，Specular，Roughness

Hair shader on Cards effective Inputs * DF：BaseColor, Scatter，Specular, Roughness，Tangent

• PT：BaseColor，Scatter，Specular, Roughness