Use the testing environment file specified in a suite

[barmax]

Fixed #20

The Laravel creates an immutable environment repository instance \Dotenv\Repository\RepositoryInterface. The instance is RepositoryBuilder from the package vlucas/phpdotenv.
When the Laravel tries change ENV-values to the .env-file from the Codeception, the immutable RepositoryBuilder does not.

[barmax]

May I ask you when the PR will merge to the main-branch?

The PR helps with my project.

[Naktibalda]

I don't understand if this change realy fixes the linked issue, but it shouldn't do any harm, so I'm merging it.
Also noone else wanted to review it.

[barmax]

I don't understand if this change realy fixes the linked issue

Ok. I explain what will change. I have followed a stack by the xDebug.

When we want use a test database in tests (my case is api tests) we should replace credentials that Laravel uses.
Tests for Laravel start with creating the Laravel application. The application loads with data from configs that get values from the .env-file and set them in the $_ENV variable.
After that we load a test env-file and we expect that the app will use values from the test .env-file.
However, when the app tries to rewrite existing values in the $_ENV an immutable writer does not it.
And when we call an endpoint, the app uses the $_ENV-values from the the original .env-file and we don't get data from the test database from a test suite.