The same repro project shows two sides of the same problem:

1) URP assets in HDRP cause endless reimporting of shadergraphs and materials (it goes to ShaderGraph people)
2) Asset Database doesn’t correctly detect the infinite loop and break out of it (it goes to Asset Database people and tracked in Case 1378193)

This current case is for issue #1 above.
The attached project has loads of URP-based shaders/materials/shadergraphs in it, and it’s the import of those that causes the infinite importing. The problem is that it’s URP assets coming into HDRP.

Steps to reproduce:
- Open the project gha-copy 3.zip (attached in comments)

Expected behaviour:
- Project opens successfully - maybe with errors/warnings in the console

Actual behaviour:
- Project gets stuck in importing.
- The text 'Importing (iteration xxx)' in the progress bar will keep increasing the iteration number into the hundreds and thousands while importing .mat and .shadergraph assets

Workaround:
- Kill the Unity process and attempt to open the project again

Reproduces on: 2021.2.0b18, 2021.2.2f1, 2022.1.0a14
Not reproduces: 2020.3.22f1

- please use both stripped and full project for verification (both can be found in the comment)

Note: when Asset Database part of the issue will be fixed (Case 1378193) - the steps to reproduce will be:
1 Open the project
2 Check in the logs for "the infinite import loop detected message" (instead of the infinite loop)