Fix bug in Institution user field (#3144)
Fix bug in Institution user field (#3144)

Fix bug in Institution user field# Description
- Quick fix. Noticed this yesterday when updating a user. Not sure how I missed it before.
- The "institution" wasn't showing up in the User Edit admin page, even though the value was OK in the db. This didn't affect setting the field using the form.

# Tests
Before:
<img width="435" alt="Screen Shot 2020-03-04 at 11 07 38 AM" src="https://user-images.githubusercontent.com/5652739/75914018-ddabe200-5e08-11ea-89e5-319f1a264e35.png">

After:
<img width="443" alt="Screen Shot 2020-03-04 at 11 08 27 AM" src="https://user-images.githubusercontent.com/5652739/75914026-e2709600-5e08-11ea-981d-60ee9e551671.png">
chanzuckerberg/idseq-web,chanzuckerberg/idseq-web,chanzuckerberg/idseq-web,chanzuckerberg/idseq-web,chanzuckerberg/idseq-web