minor #14052 Fixing bad path for class PdoSessionHandler (Clorr)

This PR was submitted for the 5.1 branch but it was merged into the 4.4 branch instead.

Discussion
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Fixing bad path for class PdoSessionHandler

Missing `Handler` directory

Commits
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09f378f Fixing bad path for class PdoSessionHandler

Author: xabbuh

session/database.rst

@@ -358,7 +358,7 @@ Preparing the Database to Store Sessions
 
 Before storing sessions in the database, you must create the table that stores
 the information. The session handler provides a method called
-:method:`Symfony\\Component\\HttpFoundation\\Session\\Storage\\PdoSessionHandler::createTable`
+:method:`Symfony\\Component\\HttpFoundation\\Session\\Storage\\Handler\\PdoSessionHandler::createTable`
 to set up this table for you according to the database engine used::
 
     try {