Steps to reproduce:
# Create a revision making sure no repository is set
# Update the revision setting a repository
# Run:
```
echo '{ "ids": [ "NEWREVID" ]}' | arc call-conduit --conduit-uri <phab_uri> --conduit-token <conduit-token> differential.query
```
and notice that: `"repositoryPHID": null,` instead of being set to the repository you just set `PHID`