[Bug Report] Importing metadata with stash ids from old versions breaks pages

[bayured]

Describe the bug
After importing metadata for objects with a stash id from older version, every page with the imported objects breaks with the requested element is null which the schema does not allow. Browsing scenes, performers or any page that references the imported objects has the same problem with that message displayed in the page body and nothing else.

To Reproduce
Steps to reproduce the behavior:

1. Export metadata for objects with stash ids from v0.27.2 or earlier
2. Import the metadata into any version after 180a0fa
3. Navigate to any page with an imported object
4. The message "the requested element is null which the schema does not allow" in the body of the page with nothing else. Non-imported objects are not displayed either. It's not possible to delete or modify the objects from the web interface

Expected behavior
Importing metadata from previous versions with stash ids and no updated_at value should default to something which doesn't break access.

Stash Version: (from Settings -> About):
v0.27.2-37-g0621d871

Additional context
Changing the imported ids' updated_at field to a date in 1970 or later in the database fixes it, e.g. for performers:
UPDATE performer_stash_ids SET updated_at = '1970-01-01T00:00:00Z' WHERE updated_at = '0001-01-01T00:00:00Z';