[GreenCity API] Fixed a bug where event dislikes were not returned correctly when retrieving an EventDto.

[Andrii-Danylenko]

Environment: OS, browser, it's version, device (for mobile devices).
Reproducible: always.
Build found: commit 1b9d570

Preconditions

1. User is authorized
2. Trying to get an event via the events/get endpoint

Steps to reproduce

1. Go to Swagger
2. Use events/get endpoint

Actual result
Even if event was disliked by any amount of users, dislike counter equal to 0

Expected result
Dislikes counter must be equal to amount of users, who disliked an event

[Andrii-Danylenko]

The bug has been fixed and is awaiting testing/merging.