Group USD Explict Save Layer Products to "USD Layer" product group

[BigRoy]

Changelog Description

USD Explicit Save Layer products should go into the USD Layer product group similar to how USD contribution workflow does that.

Additional info

Fixes #129

For context on "Explicit Layer Save Paths" see:

• USD ROP allow remapping explicit layer save paths to be remapped to AYON Entity URI #80
• Fix Collect USD Layers refactor and transfer productGroup to the extra product #59

Testing notes:

1. Create a USD publish with Explicit Save Layers that will turn into dependent products of their own.
2. Those newly created products should now by default go into a "USD Layer" product group.
3. This should work both with USD contribution workflow enabled AND disabled.

[Lypsolon]

fun fun fun.
not sure if i did it right but the pinning file json is faialing for me.

DEBUG: No staging directory on instance found.
ERROR: No staging directory found.
Traceback (most recent call last):
  File "/home/ynput/Documents/GitHub/Lyonh/AyonDev/repos/ayon-usd/client/ayon_usd/plugins/publish/extract_skeleton_pinning_json.py", line 58, in process
    staging_dir = Path(instance.data["stagingDir"])
KeyError: 'stagingDir'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/ynput/Documents/GitHub/Lyonh/AyonDev/repos/ayon-usd/client/ayon_usd/plugins/publish/extract_skeleton_pinning_json.py", line 62, in process
    staging_dir = Path(instance.data["ifdFile"]).parent
KeyError: 'ifdFile'

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/home/ynput/.local/share/AYON/dependency_packages/ayon_2406251627_linux-rocky9.zip/dependencies/pyblish/plugin.py", line 528, in __explicit_process
    runner(*args)
  File "/home/ynput/Documents/GitHub/Lyonh/AyonDev/repos/ayon-usd/client/ayon_usd/plugins/publish/extract_skeleton_pinning_json.py", line 65, in process
    raise KnownPublishError("Cannot determine staging directory.") from e
ayon_core.pipeline.publish.publish_plugins.KnownPublishError: Cannot determine staging directory.

[BigRoy]

Thanks @Lypsolon - yes, that's a bug in ayon-usd.

See: ynput/ayon-usd#75

So in this case you may be better of testing without ayon-usd in your bundle.

[Lypsolon]

nice this works.