Flaky test anonymous_themes: Couldn't write the default value for /datum/preference/name/ai (received AM)

[github-actions]

Flaky tests were detected in this test run. This means that there was a failure that was cleared when the tests were simply restarted.
Failures:

anonymous_themes: [02:06:18] Runtime in code/modules/client/preferences/_preference.dm,270: Couldn't write the default value for /datum/preference/name/ai (received AM)
proc name: read preference (/datum/preferences/proc/read_preference)
src: /datum/preferences (/datum/preferences)
call stack:
/datum/preferences (/datum/preferences): read preference(/datum/preference/name/ai (/datum/preference/name/ai))
/datum/preferences (/datum/preferences): apply prefs to(Prefs Biddle (/mob/living/carbon/human/consistent), 1)
Prefs Biddle (/mob/living/carbon/human/consistent): apply prefs job(/datum/client_interface (/datum/client_interface), /datum/job/assistant (/datum/job/assistant))
/datum/unit_test/anonymous_the... (/datum/unit_test/anonymous_themes): Run()
RunUnitTest(/datum/unit_test/anonymous_the... (/datum/unit_test/anonymous_themes), /list (/list))
RunUnitTests()
/datum/callback (/datum/callback): InvokeAsync() at code/modules/client/preferences/_preference.dm:270