Fix status in orphan feature

~~No PT/Jira story~~ JIRA story https://osraav.atlassian.net/browse/OSRA-160

- fix incorrect references to OrphanStatus/OrphanSponsorshipStatus in orphan.feature
- remove references to 'Sponsored'/'Unsponsored' as these belong to OrphanSponsorshipStatus and are never set manually
- add tests for fields in index view

## JIRA
OSRA-160 #Code-Review