remove versionadded directive for Symfony 5.2

Author: xabbuh

http_client.rst

@@ -1695,10 +1695,6 @@ has many safety checks that will throw a ``LogicException`` if the chunk
 passthru doesn't behave correctly; e.g. if a chunk is yielded after an ``isLast()``
 one, or if a content chunk is yielded before an ``isFirst()`` one, etc.
 
-.. versionadded:: 5.2
-
-    :class:`Symfony\\Component\\HttpClient\\AsyncDecoratorTrait` was introduced in Symfony 5.2.
-
 Testing
 -------