minor #54857 [Messenger] Fix missing import (alexandre-daubois)

This PR was merged into the 7.1 branch.

Discussion
----------

[Messenger] Fix missing import

| Q             | A
| ------------- | ---
| Branch?       | 7.1
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Issues        | -
| License       | MIT

[Fixes CI](https://github.com/symfony/symfony/actions/runs/8980645540/job/24664656941#step:8:1304)

Commits
-------

36a1636 [Messenger] Remove ContainerInterface mock

src/Symfony/Component/Messenger/Tests/FailureIntegrationTest.php

@@ -433,22 +433,13 @@ public function testStampsAddedByMiddlewaresDontDisappearWhenValidationFails()
             'transport1' => $transport1,
         ];
 
-        $locator = $this->createMock(ContainerInterface::class);
-        $locator->expects($this->any())
-            ->method('has')
-            ->willReturn(true);
-        $locator->expects($this->any())
-            ->method('get')
-            ->willReturnCallback(fn ($transportName) => $transports[$transportName]);
+        $locator = new Container();
+        $locator->set('transport1', $transport1);
+
         $senderLocator = new SendersLocator([], $locator);
 
-        $retryStrategyLocator = $this->createMock(ContainerInterface::class);
-        $retryStrategyLocator->expects($this->any())
-            ->method('has')
-            ->willReturn(true);
-        $retryStrategyLocator->expects($this->any())
-            ->method('get')
-            ->willReturn(new MultiplierRetryStrategy(1));
+        $retryStrategyLocator = new Container();
+        $retryStrategyLocator->set('transport1', new MultiplierRetryStrategy(1));
 
         $violationList = new ConstraintViolationList([new ConstraintViolation('validation failed', null, [], null, null, null)]);
         $validator = $this->createMock(ValidatorInterface::class);