minor #6268 Minor change to make some code more readable (javiereguiluz)

This PR was merged into the 4.x branch.

Discussion
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Minor change to make some code more readable

PHP-CS-Fixer is complaining about some issue in that line (see https://github.com/EasyCorp/EasyAdminBundle/actions/runs/8726644807/job/23942389012?pr=6267) and the code is a bit complex to read ... so let's simplify it.

Commits
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7dea640 Minor change to make some code more readable

src/Filter/Configurator/EntityConfigurator.php

@@ -39,9 +39,17 @@ public function configure(FilterDto $filterDto, ?FieldDto $fieldDto, EntityDto $
             // because an empty filter value would always return no result
             $numberOfRequiredJoinColumns = \count(array_filter(
                 $doctrineMetadata->get('joinColumns'),
-                // Doctrine ORM 3.x changed the returned type from array to JoinColumnMapping
-                static fn (array|JoinColumnMapping $joinColumn): bool => false === (($joinColumn instanceof JoinColumnMapping ? $joinColumn->nullable ?? false : $joinColumn['nullable'] ?? false)))
-            );
+                static function (array|JoinColumnMapping $joinColumn): bool {
+                    // Doctrine ORM 3.x changed the returned type from array to JoinColumnMapping
+                    if ($joinColumn instanceof JoinColumnMapping) {
+                        $isNullable = $joinColumn->nullable ?? false;
+                    } else {
+                        $isNullable = $joinColumn['nullable'] ?? false;
+                    }
+
+                    return false === $isNullable;
+                }
+            ));
 
             $someJoinColumnsAreNullable = \count($doctrineMetadata->get('joinColumns')) !== $numberOfRequiredJoinColumns;