The postprocessing sample under HDRP package conflicts with PostProcessing unity package in package manager. Refer the attached screenshot

Steps to reproduce:
1) Create a new project with HDRP template
2) Window > Package Manager
3) HDRP > Import "Additional Post-processing data" sample
4) Install package PostProcessing

Actual result: GUID conflict errors are thrown
Expected result: No errors should be thrown

Occurring on: 2020.2.0a4, 2020.1.0b3, 2019.3.4f1, 2019.2.11f1

Postprocessing package version: 2.3.0, 2.2.2, 2.2.1

HDRP package version: 8.0.1, 7.2.0, 7.1.8, 7.1.7

Environment: Both Windows and Mac

Stack Trace:
GUID [3884f7a2d04ffe8409ad9200b275896f] for asset 'Packages/com.unity.postprocessing/PostProcessing/Textures/Lens Dirt/LensDirt01.png' conflicts with:
'Assets/Samples/High Definition RP/7.1.8/Additional Post-processing Data/Lens Dirt/LensDirt01.png' (current owner)
We can't assign a new GUID because the asset is in an immutable folder. The asset will be ignored.