Fix ORM xmlns (#1628)

Author: jordisala1991

src/Resources/config/doctrine/BaseUser.orm.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<doctrine-mapping xmlns="https://doctrine-project.org/schemas/orm/doctrine-mapping" xmlns:xsi="https://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="https://doctrine-project.org/schemas/orm/doctrine-mapping https://doctrine-project.org/schemas/orm/doctrine-mapping.xsd">
+<doctrine-mapping xmlns="http://doctrine-project.org/schemas/orm/doctrine-mapping" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="https://doctrine-project.org/schemas/orm/doctrine-mapping https://www.doctrine-project.org/schemas/orm/doctrine-mapping.xsd">
     <mapped-superclass name="Sonata\UserBundle\Entity\BaseUser">
         <field name="username" column="username" type="string" length="180"/>
         <field name="usernameCanonical" column="username_canonical" type="string" length="180" unique="true"/>