Failing api4 test api.v4.Action.CreateWithOptionGroupTest.testWithCustomDataForMultipleContacts
So the BAO CustomField looks maybe buggy to me. At this line, it says for almost any type except text, let's see about creating an option group. And then it says, partly, if it's a new field and there's no option_group_id specified, let's create a dummy one for it with name
based on timestamp. Unless you've passed in the magic number 2.
Since in unit tests the timestamp is almost constant, you get a duplicate sometimes if the second hasn't rolled over yet.
Or, the tests should clean up the dummy option groups too.