minor symfony#59799 [Validator] Fix incorrect assertion in WhenTest (alexandre-daubois)

This PR was merged into the 6.4 branch.

Discussion
----------

[Validator] Fix incorrect assertion in `WhenTest`

| Q             | A
| ------------- | ---
| Branch?       | 6.4
| Bug fix?      | no
| New feature?  | no
| Deprecations? | no
| Issues        | -
| License       | MIT

Commits
-------

e71a278 [Validator] Fix incorrect assertion in `WhenTest`

Author: nicolas-grekas

src/Symfony/Component/Validator/Tests/Constraints/WhenTest.php

@@ -89,7 +89,7 @@ public function testAnnotations()
 
         [$barConstraint] = $metadata->properties['bar']->getConstraints();
 
-        self::assertInstanceOf(When::class, $fooConstraint);
+        self::assertInstanceOf(When::class, $barConstraint);
         self::assertSame('false', $barConstraint->expression);
         self::assertEquals([
             new NotNull([
@@ -161,7 +161,7 @@ public function testAttributes()
 
         [$barConstraint] = $metadata->properties['bar']->getConstraints();
 
-        self::assertInstanceOf(When::class, $fooConstraint);
+        self::assertInstanceOf(When::class, $barConstraint);
         self::assertSame('false', $barConstraint->expression);
         self::assertEquals([
             new NotNull([