minor #13477 [FrameworkBundle] Deprecate flashbag and attributebag services (javiereguiluz)

This PR was merged into the master branch.

Discussion
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[FrameworkBundle] Deprecate flashbag and attributebag services

Fixes #13467.

Commits
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8f0630a [FrameworkBundle] Deprecate flashbag and attributebag services

Author: javiereguiluz

session.rst

@@ -182,7 +182,7 @@ the default ``AttributeBag`` by the ``NamespacedAttributeBag``:
         session:
             public: true
             class: Symfony\Component\HttpFoundation\Session\Session
-            arguments: ['@session.storage', '@session.namespacedattributebag', '@session.flash_bag']
+            arguments: ['@session.storage', '@session.namespacedattributebag']
 
         session.namespacedattributebag:
             class: Symfony\Component\HttpFoundation\Session\Attribute\NamespacedAttributeBag