bug symfony#44473 [Validator] Restore default locale in ConstraintValidatorTestCase (rodnaph)

This PR was merged into the 4.4 branch.

Discussion
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[Validator] Restore default locale in ConstraintValidatorTestCase

| Q             | A
| ------------- | ---
| Branch?       | 6.1
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Tickets       | N/A
| License       | MIT
| Doc PR        | N/A

Previously this code was not resetting the locale after changing it to `en` - which affected other tests which relied on this value being the configured value (however it was configured).

This mirrors the pattern used for the timezone, storing it to be reset on tearDown.

I've based this on 6.1. If it's valid, I'm unsure if it's classed a bug, or needs UPGRADE notes?

Commits
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77267c0 restore the overriden locale on tearDown - avoid interfering with any configured value

Author: fancyweb

src/Symfony/Component/Validator/Test/ConstraintValidatorTestCase.php

@@ -58,6 +58,7 @@ abstract class ConstraintValidatorTestCase extends TestCase
     protected $propertyPath;
     protected $constraint;
     protected $defaultTimezone;
+    private $defaultLocale;
 
     private function doSetUp()
     {
@@ -76,6 +77,7 @@ private function doSetUp()
         $this->validator = $this->createValidator();
         $this->validator->initialize($this->context);
 
+        $this->defaultLocale = \Locale::getDefault();
         \Locale::setDefault('en');
 
         $this->setDefaultTimezone('UTC');
@@ -84,6 +86,8 @@ private function doSetUp()
     private function doTearDown()
     {
         $this->restoreDefaultTimezone();
+
+        \Locale::setDefault($this->defaultLocale);
     }
 
     protected function setDefaultTimezone($defaultTimezone)