minor #14877 [Validator] Change the example to be consistent with the rest (wkania)

This PR was merged into the 5.1 branch.

Discussion
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[Validator] Change the example to be consistent with the rest

Other examples do not use key 'value'.

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Commits
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a423947 [Validator] Change the example to be consistent with the rest

Author: OskarStark

reference/constraints/AtLeastOneOf.rst

@@ -141,7 +141,7 @@ The following constraints ensure that:
                         new Assert\Count(['min' => 3]),
                         new Assert\All([
                             'constraints' => [
-                                new Assert\GreaterThanOrEqual(['value' => 5]),
+                                new Assert\GreaterThanOrEqual(5),
                             ],
                         ]),
                     ],