Bug: Custom SIT editor crashes after adding LuhnCheck validator

A reproducible issue has been identified in Microsoft Purview related to the built-in LuhnCheck validator within a Custom Sensitive Information Type (Custom SIT).

A custom SIT can be created, saved, and edited normally when it uses a regular expression without validators.

However, after adding the LuhnCheck validator, saving the SIT, exiting the editor, and then reopening the SIT to edit the regular expression, the Microsoft Purview portal displays a completely blank screen and no longer allows access to the configuration.

Steps to Reproduce

1. Create a new Custom Sensitive Information Type.
2. Add a regular expression as the primary element.
3. Save the SIT.
4. Reopen it and edit the regular expression.
5. Confirm that the editor works correctly.
6. Add the built-in LuhnCheck validator.
7. Save the SIT.
8. Exit the editor.
9. Reopen the SIT.
10. Attempt to edit the regular expression again.

Actual Result

The Microsoft Purview portal displays a blank screen, and the editor fails to load.