[Validator] Fix GroupSequenceProvider annotation

Author: enumag

Constraints/GroupSequence.php

@@ -57,7 +57,7 @@ class GroupSequence
     /**
      * The groups in the sequence.
      *
-     * @var string[]|array[]|GroupSequence[]
+     * @var string[]|string[][]|GroupSequence[]
      */
     public $groups;
 

GroupSequenceProviderInterface.php

@@ -22,7 +22,7 @@ interface GroupSequenceProviderInterface
      * Returns which validation groups should be used for a certain state
      * of the object.
      *
-     * @return string[]|GroupSequence An array of validation groups
+     * @return string[]|string[][]|GroupSequence An array of validation groups
      */
     public function getGroupSequence();
 }