Setup Heroku to run Django unit tests in parallel

I am currently working on a Django project and have deployed my application on Heroku.

I want to optimize my CI/CD pipeline by running my Django unit tests in parallel (I’m using pytest and I’d like to keep using it). Could someone guide me on how to properly set up parallel test execution?

The following is my app.json file:

{
  ...
  "environments": {
    "review": {
      ...
    },
    "test": {
      "scripts": {
        "test": "pytest -v --cov=app-name --cov-fail-under=90",
        "integration-test": "pytest -v -m integration"
      },
      "env": {
        ...
      },
      "formation": {
        "test": {
          "quantity": 1,
          "size": "standard-1x"
        }
      },
      "buildpacks": [
        {
          "url": "heroku/python"
        }
      ]
    }
  }
}