Ukrainian: incorrect display of error if create poll with same variants

Steps to reproduce:
1. Sign in
2. Choose the ukranian language in the upper left corner
3. Create a new topic with a poll
4. Fill in topic title, message content, poll and in the option list create several same variants
5. Click 'Save'

ACTUAL RESULT: Error message under option list field '

'

EXPECTED RESULT: Error message under option list field 'опції голосування не можуть містити дублікати'