Flaky test failure with no obvious source

[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:

[Drulikar]

runtime error: pick() from empty list
proc name: GenerateSymptoms (/datum/disease/advance/proc/GenerateSymptoms)
source file: code/datums/diseases/advance/advance.dm,163
usr: null
src: Unknown (/datum/disease/advance)
call stack:
Unknown (/datum/disease/advance): GenerateSymptoms(2, 0)
Unknown (/datum/disease/advance): New(0, null)
the random culture bottle (/obj/item/reagent_container/glass/bottle/random): Initialize(0)
Atoms (/datum/controller/subsystem/atoms): InitAtom(the random culture bottle (/obj/item/reagent_container/glass/bottle/random), 0, /list (/list))
the random culture bottle (/obj/item/reagent_container/glass/bottle/random): New(0)
/datum/unit_test/create_and_de... (/datum/unit_test/create_and_destroy): Run()
RunUnitTest(/datum/unit_test/create_and_de... (/datum/unit_test/create_and_destroy), /list (/list))
RunUnitTests()
/datum/callback (/datum/callback): InvokeAsync()
runtime error: We did not have any symptoms before generating properties.
proc name: GenerateProperties (/datum/disease/advance/proc/GenerateProperties)
source file: code/datums/diseases/advance/advance.dm,186
usr: null
src: Unknown (/datum/disease/advance)
call stack:
Unknown (/datum/disease/advance): GenerateProperties()
Unknown (/datum/disease/advance): Refresh(0)
Unknown (/datum/disease/advance): New(0, null)
the random culture bottle (/obj/item/reagent_container/glass/bottle/random): Initialize(0)
Atoms (/datum/controller/subsystem/atoms): InitAtom(the random culture bottle (/obj/item/reagent_container/glass/bottle/random), 0, /list (/list))
the random culture bottle (/obj/item/reagent_container/glass/bottle/random): New(0)
/datum/unit_test/create_and_de... (/datum/unit_test/create_and_destroy): Run()
RunUnitTest(/datum/unit_test/create_and_de... (/datum/unit_test/create_and_destroy), /list (/list))
RunUnitTests()
/datum/callback (/datum/callback): InvokeAsync()
runtime error: Our properties were empty or null!
proc name: AssignProperties (/datum/disease/advance/proc/AssignProperties)
source file: code/datums/diseases/advance/advance.dm,214
usr: null
src: Unknown (/datum/disease/advance)
call stack:
Unknown (/datum/disease/advance): AssignProperties(/list (/list))
Unknown (/datum/disease/advance): Refresh(0)
Unknown (/datum/disease/advance): New(0, null)
the random culture bottle (/obj/item/reagent_container/glass/bottle/random): Initialize(0)
Atoms (/datum/controller/subsystem/atoms): InitAtom(the random culture bottle (/obj/item/reagent_container/glass/bottle/random), 0, /list (/list))
the random culture bottle (/obj/item/reagent_container/glass/bottle/random): New(0)
/datum/unit_test/create_and_de... (/datum/unit_test/create_and_destroy): Run()
RunUnitTest(/datum/unit_test/create_and_de... (/datum/unit_test/create_and_destroy), /list (/list))
RunUnitTests()
/datum/callback (/datum/callback): InvokeAsync()