`referred_to` field may not be getting updated properly

[mlissner]

Sometimes cases get new judges. An example of this can be found here:

https://www.courtlistener.com/docket/67762100/novartis-pharmaceuticals-corporation-v-becerra/

Note in numberless entry on Sept 5, 2023:

Judge Zahid N. Quraishi and Magistrate Judge Douglas E. Arpert added. (jjc, )

But then in numberless entry on Feb 1, 2024:

Magistrate Judge J. Brendan Day added. Magistrate Judge Douglas E. Arpert no longer assigned to case. (jjc, )

In the docket, as of today, the referred_to value points to judge:

https://www.courtlistener.com/api/rest/v4/people/9375/

That's Douglas Alpert, the first judge.

But the referred_to_str value is:

J. Brendan Day

Which is correct. A client points out that we have about 20,000 of these issues.

One theory is that this happens when we don't have a judge, as is the case with Judge Day:

https://www.courtlistener.com/?type=p&q=Brendan%20Day&type=p&order_by=score%20desc

(Returns zero results.)

Maybe we just need to clear out referred_to when we update referred_to_str?

[mlissner]

This might be a dup of: https://github.com/freelawproject/courtlistener/issues/4437