EZP-28527: Fix ContentTypeFormProcessorTest::testAddFieldDefinition test

[webhdx]

JIRA: https://jira.ez.no/browse/EZP-28527

Description

Test were broken by #187, this PR fixes failing test. This PR has to be merged up to the master.

[andrerom]

@webhdx seesm to still be some issue on PHP 5.6 on travis:

1) EzSystems\RepositoryForms\Tests\Form\Processor\ContentTypeFormProcessorTest::testAddFieldDefinition

Expectation failed for method name is equal to <string:addFieldDefinition> when invoked 1 time(s)

Parameter 1 for invocation eZ\Publish\API\Repository\ContentTypeService::addFieldDefinition(eZ\Publish\Core\Repository\Values\ContentType\ContentTypeDraft Object (...), eZ\Publish\API\Repository\Values\ContentType\FieldDefinitionCreateStruct Object (...)) does not match expected value.

Failed asserting that two objects are equal.
--- Expected
+++ Actual
@@ @@
 eZ\Publish\API\Repository\Values\ContentType\FieldDefinitionCreateStruct Object (
     'fieldTypeIdentifier' => 'ezstring'
-    'identifier' => 'new_ezstring_3'
+    'identifier' => 'new_ezstring_1'

[webhdx]

@andrerom Is this only on PHP 5.6? It's not possible as this PR is fixing mentioned issue.

PHPUnit run locally for this PR:

[andrerom]

restarting the job to see if travis is doing hick-ups on us, but indeed this is strange as the error is the same as before your fix. Seems also this branch is running on very old version of travis, but we can take that separately later.

So merging this so we can see what is remaining afterwards, will merge up to master.