Number of teams in leaderboard works only on the first tab

See the screenshot from [this leaderboard](https://ods.ai/competitions/sberbank-covid19-forecast/leaderboard):
<img width="435" alt="Screenshot 2020-05-21 at 14 02 05" src="https://user-images.githubusercontent.com/152387/82552973-da083b80-9b6b-11ea-80bd-7965eeb4355c.png">