Mark classes as final

tests/AppKernel.php

@@ -9,7 +9,7 @@ use Symfony\Bundle\FrameworkBundle\FrameworkBundle;
 use Symfony\Component\Config\Loader\LoaderInterface;
 use Symfony\Component\HttpKernel\Kernel;
 
-class AppKernel extends Kernel
+final class AppKernel extends Kernel
 {
     /**
      * @return array
@@ -30,3 +30,4 @@ class AppKernel extends Kernel
         $loader->load(__DIR__.'/config_'.$this->getEnvironment().'.yml');
     }
 }
+

tests/Service/GeocodeTest.php

@@ -14,7 +14,7 @@ use Symfony\Bundle\FrameworkBundle\Test\KernelTestCase;
 /**
  * We sleep 1 second after API calls to prevent breaking the API T&Cs.
  */
-class GeocodeTest extends KernelTestCase
+final class GeocodeTest extends KernelTestCase
 {
     // Buckingham Palace
     private const string POSTCODE = 'SW1A 1AA';

tests/Trait/MappableTraitTest.php

@@ -8,7 +8,7 @@ use Pcm\GeocodeBundle\Entity\Interface\MappableInterface;
 use Pcm\GeocodeBundle\Entity\Trait\MappableTrait;
 use PHPUnit\Framework\TestCase;
 
-class MappableTraitTest extends TestCase
+final class MappableTraitTest extends TestCase
 {
     private const float COORD = 123.456;