Saving a Viewfield config results in WSOD

[omahane]

Describe the defect

When saving a Viewfield field settings, the result is a WSOD with the following message:

The website encountered an unexpected error. Try again later.

TypeError: uasort(): Argument #1 ($array) must be of type array, null given in uasort() (line 65 of core/lib/Drupal/Core/Entity/EntityReferenceSelection/SelectionPluginManager.php).

To Reproduce

Steps to reproduce the behavior:

1. Go to https://main-8ry6zt2asg946vdfuiryyamuc9gkuyzc.demo.cms.va.gov/admin/structure/types/manage/vamc_system_register_for_care/fields/node.vamc_system_register_for_care.field_non_clinical_services
2. Click 'Save'
3. Confirm the WSOD

AC / Expected behavior

The configuration should save without error.

Context

I have been working on an issue that involves a Viewfield and only began experiencing this issue today. I would guess that some change in the last 5 days or so is responsible.