minor symfony#27771 [Form] relax fixtures for forward compat (nicolas-grekas)

This PR was merged into the 3.4 branch.

Discussion
----------

[Form] relax fixtures for forward compat

| Q             | A
| ------------- | ---
| Branch?       | 3.4
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

Required to make symfony#27768 green.

Commits
-------

2258ce4 [Form] relax fixtures for forward compat

Author: Robin Chalas

src/Symfony/Component/Form/Tests/Fixtures/Descriptor/default_option_with_normalizer.txt

@@ -15,7 +15,7 @@ Symfony\Component\Form\Extension\Core\Type\ChoiceType (choice_translation_domain
  ---------------- --------------------%s 
   Allowed values   -                  %s 
  ---------------- --------------------%s 
-  Normalizer       Closure {          %s 
+  Normalizer       Closure%s{         %s 
                      parameters: 2    %s 
                      file: "%s%eExtension%eCore%eType%eChoiceType.php"  
                      line: "%s to %s" %s 

src/Symfony/Component/Form/Tests/Fixtures/Descriptor/overridden_option_with_default_closures.txt

@@ -8,12 +8,12 @@ Symfony\Component\Form\Tests\Console\Descriptor\FooType (empty_data)
   Default          Value: null          %s 
                                         %s 
                    Closure(s): [        %s 
-                     Closure {          %s 
+                     Closure%s{         %s 
                        parameters: 1    %s 
                        file: "%s%eExtension%eCore%eType%eFormType.php"                     
                        line: "%s to %s" %s 
                      },                 %s 
-                     Closure {          %s 
+                     Closure%s{         %s 
                        parameters: 2    %s 
                        file: "%s%eTests%eConsole%eDescriptor%eAbstractDescriptorTest.php"  
                        line: "%s to %s" %s 

src/Symfony/Component/Form/Tests/Fixtures/Descriptor/required_option_with_allowed_values.txt

@@ -16,7 +16,7 @@ Symfony\Component\Form\Tests\Console\Descriptor\FooType (foo)
                      "baz"            %s 
                    ]                  %s 
  ---------------- --------------------%s 
-  Normalizer       Closure {          %s 
+  Normalizer       Closure%s{         %s 
                      parameters: 2    %s 
                      file: "%s%eTests%eConsole%eDescriptor%eAbstractDescriptorTest.php"  
                      line: "%s to %s" %s