minor #54785 Remove calls to TestCase::iniSet() and calls to deprecated methods of MockBuilder (alexandre-daubois)

This PR was merged into the 5.4 branch.

Discussion
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Remove calls to `TestCase::iniSet()` and calls to deprecated methods of `MockBuilder`

| Q             | A
| ------------- | ---
| Branch?       | 5.4
| Bug fix?      | no
| New feature?  | no
| Deprecations? | no
| Issues        | -
| License       | MIT

Last round (before new deprecations 🙂). All deprecations [listed here](https://github.com/sebastianbergmann/phpunit/blob/main/DEPRECATIONS.md) should be gone.

Commits
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4d5065ddd9 Remove calls to `TestCase::iniSet()` and calls to deprecated methods of `MockBuilder`

Author: xabbuh

Tests/Fixtures/MockableRepository.php

@@ -0,0 +1,21 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <[email protected]>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Bridge\Doctrine\Tests\Fixtures;
+
+use Doctrine\ORM\EntityRepository;
+
+class MockableRepository extends EntityRepository
+{
+    public function findByCustom()
+    {
+    }
+}

Tests/Validator/Constraints/UniqueEntityValidatorTest.php

@@ -28,6 +28,7 @@
 use Symfony\Bridge\Doctrine\Tests\Fixtures\DoubleNameEntity;
 use Symfony\Bridge\Doctrine\Tests\Fixtures\DoubleNullableNameEntity;
 use Symfony\Bridge\Doctrine\Tests\Fixtures\Employee;
+use Symfony\Bridge\Doctrine\Tests\Fixtures\MockableRepository;
 use Symfony\Bridge\Doctrine\Tests\Fixtures\Person;
 use Symfony\Bridge\Doctrine\Tests\Fixtures\SingleIntIdEntity;
 use Symfony\Bridge\Doctrine\Tests\Fixtures\SingleIntIdNoToStringEntity;
@@ -97,14 +98,10 @@ protected function createRegistryMock($em = null)
 
     protected function createRepositoryMock()
     {
-        $repository = $this->getMockBuilder(EntityRepository::class)
+        return $this->getMockBuilder(MockableRepository::class)
             ->disableOriginalConstructor()
-            ->onlyMethods(['find', 'findAll', 'findOneBy', 'findBy', 'getClassName'])
-            ->addMethods(['findByCustom'])
-            ->getMock()
-        ;
-
-        return $repository;
+            ->onlyMethods(['find', 'findAll', 'findOneBy', 'findBy', 'getClassName', 'findByCustom'])
+            ->getMock();
     }
 
     protected function createEntityManagerMock($repositoryMock)