pytest and pytest-xdist plugin with --snapshot-update -n auto deletes all snapshots on parallel executions

[Sharu95]

Description

Currently working on optimizing some pipelines where I discovered that pytest + pytest-xdist behaves different with the -n flag combined with --snapshot-update. The issue arised while using tox, but is replicated with only pytest, pytest-xdist and syrupy. A minimal codebase is provided to replicate the results further down.

Actual outcome
All snapshots (new and old) are deleted when tests are run with --snapshot-update -n auto
Expected outcome
All old snapshots should not be deleted and a new snapshot should be added with --snapshot-update -n auto

Steps to reproduce

1. Create initial snapshots with pytest --snapshot-update
2. Add a new test to the test-file
3. Run pytest --snapshot-update -n auto to run tests in parallel, which deletes snapshots

Screenshot of steps

System information

Name	Version
python	3.7.12
pip	21.3.1
syrupy	1.7.3
pytest-xdist	2.5.0
pytest	6.2.5
MacBook Pro 2016	MacOS Big Sur 11.6

piplist.txt
requirements.txt
Full code/minimum example: codebase.zip

[RonnyPfannschmidt]

duplicate of syrupy-project/syrupy#535