Animation Rigging package sample project is not under the specified folder hierarchy Assets > Samples. All the packages with sample projects should follow the folder hierarchy "Assets/Samples/Package Name/Version/Sample Name" according to "Package sample support" guideline doc. Refer the attached screenshot

Steps to reproduce:
1) Create a new project
2) Window > Package Manager
3) Install Animation Rigging package
4) Import sample project

Actual result: The sample project is imported under "Assets > Unity"

Expected result: The sample project is imported under the specified folder hierarchy "Assets/Samples/Package Name/Version/Sample Name"

Occurring in: 2020.2.0b2, 2020.1.4f1, 2019.4.9f1 with Animation rigging package version 1.0.3, 1.0.2 and 0.2.7 preview

Environment: Both Mac and Windows