use_prf flag is mandatory

[isoboroff]

If you don't have an opt for use_prf, the search action doesn't work:

$ python run.py search --repo osirrc2019/indri --tag v0.1.0 --output out/indri --qrels   qrels/qrels.robust04.txt --topic topics/topics.robust04.txt --collection robust04 --top_k 1000 --opts out_file_name="robust.dir1000" rule="method:dirichlet,mu:1000" topic_type="title"
Starting container from saved image...
Logs for search in container with ID     6bddc714a2a20a42155661d83dcdeda08b167f1ee40589c461b36014c58f16b4...
Searching ...
Traceback (most recent call last):
  File "/search", line 20, in <module>
    use_prf = args.json["opts"]["use_prf"]
KeyError: 'use_prf'
Evaluating results using trec_eval...
$

[isoboroff]

If I add use_prf=0 to the opts it runs.

[isoboroff]

Adding 'use_prf=1' makes the run take a long time, but with zero output in the runfile and no error messages.