minor #10843 Update pdo_session_storage.rts (andriusUlins)

This PR was submitted for the 4.2 branch but it was merged into the 3.4 branch instead (closes #10843).

Discussion
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Update pdo_session_storage.rts

Argument `DSN` for `PdoSessionHandler` should be seperated by semicolon instead of comma.
Source: `http://php.net/manual/en/pdo.connections.php`

Also added extra parameter example `port`

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Commits
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963429c Update pdo_session_storage.rts

Author: javiereguiluz

doctrine/pdo_session_storage.rst

@@ -24,7 +24,7 @@ To use it, first register a new handler service:
             Symfony\Component\HttpFoundation\Session\Storage\Handler\PdoSessionHandler:
                 public:    false
                 arguments:
-                    - 'mysql:dbname=mydatabase, host=myhost'
+                    - 'mysql:dbname=mydatabase; host=myhost; port=myport'
                     - { db_username: myuser, db_password: mypassword }
 
     .. code-block:: xml
@@ -56,7 +56,7 @@ To use it, first register a new handler service:
 
         $storageDefinition = $container->register(PdoSessionHandler::class)
             ->setArguments(array(
-                'mysql:dbname=mydatabase, host=myhost',
+                'mysql:dbname=mydatabase; host=myhost; port=myport',
                 array('db_username' => 'myuser', 'db_password' => 'mypassword'),
             ))
         ;
@@ -119,7 +119,7 @@ a second array argument to ``PdoSessionHandler``:
             Symfony\Component\HttpFoundation\Session\Storage\Handler\PdoSessionHandler:
                 public:    false
                 arguments:
-                    - 'mysql:dbname=mydatabase, host=myhost'
+                    - 'mysql:dbname=mydatabase; host=myhost; port=myport'
                     - { db_table: 'sessions', db_username: 'myuser', db_password: 'mypassword' }
 
     .. code-block:: xml
@@ -152,7 +152,7 @@ a second array argument to ``PdoSessionHandler``:
 
         $container->register(PdoSessionHandler::class)
             ->setArguments(array(
-                'mysql:dbname=mydatabase, host=myhost',
+                'mysql:dbname=mydatabase; host=myhost; port=myport',
                 array('db_table' => 'sessions', 'db_username' => 'myuser', 'db_password' => 'mypassword')
             ))
         ;