PHPUnit risky tests

[jefferson-jscode]

I was getting the following error in 6 of 7 tests: Test code or tested code did not (only) close its own output buffers.

I "fixed" the problem by using the create() method instead of image().

From this: UploadedFile::fake()->image($filename);
To this: UploadedFile::fake()->create($filename);

[jefferson-jscode]

Solved the problem installing the gd extension:
sudo apt install php8.1-gd