minor #8333 Update proxy_examples.rst (atailouloute)

This PR was merged into the 2.7 branch.

Discussion
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Update proxy_examples.rst

Add missing namespace;

Commits
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f32b6fa Update proxy_examples.rst

Author: xabbuh

session/proxy_examples.rst

@@ -61,6 +61,7 @@ Symfony to use your own session handler instead of the default one:
         <?xml version="1.0" encoding="UTF-8" ?>
         <container xmlns="http://symfony.com/schema/dic/services"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+            xmlns:framework="http://symfony.com/schema/dic/symfony"
             xsi:schemaLocation="http://symfony.com/schema/dic/services
                 http://symfony.com/schema/dic/services/services-1.0.xsd">