minor Sylius#16654 [API] Fix ShopUser docs example (mpysiak)

This PR was merged into the 1.13 branch.

Discussion
----------

| Q               | A
|-----------------|-----
| Branch?         | 1.13
| Bug fix?        | yes
| New feature?    | no
| BC breaks?      | no
| Deprecations?   | no
| Related tickets | fixes #X, partially #Y, mentioned in #Z
| License         | MIT

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Fix for Customer admin POST example in the docs


Commits
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  Fix ShopUser docs example

src/Sylius/Bundle/ApiBundle/Resources/config/api_resources/ShopUser.xml

@@ -30,5 +30,11 @@
         <collectionOperations/>
 
         <property name="id" identifier="true" writable="false" />
+        <property name="verifiedAt" >
+            <attribute name="openapi_context">
+                <attribute name="type">boolean</attribute>
+                <attribute name="example">true</attribute>
+            </attribute>
+        </property>
     </resource>
 </resources>