Merge branch '5.1' into 5.2

* 5.1:
  Remove white space
  Minor: Fix quotes
  Minor: Remove extra space in the config example
  Restore version-added in string

Author: OskarStark

components/serializer.rst

@@ -681,7 +681,7 @@ defines a ``Person`` entity with a ``firstName`` property:
 This custom mapping is used to convert property names when serializing and
 deserializing objects::
 
-    $serialized = $serializer->serialize(new Person("Kévin"), 'json');
+    $serialized = $serializer->serialize(new Person('Kévin'), 'json');
     // {"customer_name": "Kévin"}
 
 Serializing Boolean Attributes

components/string.rst

@@ -8,6 +8,10 @@ The String Component
     The String component provides a single object-oriented API to work with
     three "unit systems" of strings: bytes, code points and grapheme clusters.
 
+.. versionadded:: 5.0
+
+    The String component was introduced in Symfony 5.0.
+
 Installation
 ------------
 

configuration/using_parameters_in_dic.rst

@@ -106,7 +106,7 @@ be injected with this parameter via the extension as follows::
     {
         private $debug;
 
-        public function  __construct($debug)
+        public function __construct($debug)
         {
             $this->debug = (bool) $debug;
         }

mailer.rst

@@ -1046,7 +1046,7 @@ you have a transport called ``async``, you can route the message there:
                     async: "%env(MESSENGER_TRANSPORT_DSN)%"
 
                 routing:
-                    'Symfony\Component\Mailer\Messenger\SendEmailMessage':  async
+                    'Symfony\Component\Mailer\Messenger\SendEmailMessage': async
 
     .. code-block:: xml