PHPUnit settings are not configured.

To configure PHPUnit settings, you need to follow these steps:

1. Install PHPUnit using Composer. Run the following command in your project directory:

composer require --dev phpunit/phpunit

2. Once PHPUnit is installed, create a `phpunit.xml` file in the root directory of your project. This file should contain the configuration settings for PHPUnit.

3. Open the `phpunit.xml` file and add the following lines:

<phpunit>
    <testsuites>
        <testsuite name="My Test Suite">
            <directory>tests</directory>
        </testsuite>
    </testsuites>
</phpunit>

4. In the above code, replace "My Test Suite" with the name of your test suite. Also, make sure that the `directory` tag points to the directory where your test files are located.

5. Save the `phpunit.xml` file and run the following command to execute your tests:

./vendor/bin/phpunit

6. If everything is configured correctly, PHPUnit will run your tests and display the results.