How to write docker-compose.yml with db for tests?

Question

Software design

There is a dockerized project, docker-compose.yml looks like this:

version: '3'
services:
  web:
    /*Основное приложение*/
  db:
    /*База данных*/
  phpmyadmin:
    /*PHPMyAdmin*/
    ports:
      - 8080:80
    depends_on:
      - db

I want to cover the project with tests. As I understand it, the tests need their own database. Here I see 2 options:
1) The most obvious: Create two new services: test_db and, accordingly, phpmyadmin for it

test_db:
      /*База данных*/
  test_phpmyadmin:
    /*PHPMyAdmin*/
    ports:
      - 8080:80
    depends_on:
      - test_db

Isn't it bold to single out two services specifically for tests? Or is it considered normal?
2) On the same old db service, create a second database. But here the problem is that there is no normal way to do this through the enviroment, and you will have to come up with crutches with the entrypoint. For example: https://forums.docker.com/t/multiple-databases-in-...
What would be the best approach in this situation?