[Mailer] Moved version notice to after note for require_tls

As requested by OskarStark.

Author: ssddanbrown

mailer.rst

@@ -423,10 +423,6 @@ setting the ``auto_tls`` option to ``false`` in the DSN::
 Require use of TLS
 ~~~~~~~~~~~~~~~~~~
 
-.. versionadded:: 7.3
-
-    The option to require TLS was introduced in Symfony 7.3.
-
 You may want to ensure TLS is used, either directly or via ``STARTTLS``,
 for sending mail over SMTP regardless of other options set or SMTP server
 support. You can set TLS as required by calling ``setRequireTls(true)``
@@ -443,6 +439,10 @@ with the SMTP server.
 
     This setting only works when the ``smtp://`` protocol is used.
 
+.. versionadded:: 7.3
+
+    The option to require TLS was introduced in Symfony 7.3.
+
 Binding to IPv4 or IPv6
 ~~~~~~~~~~~~~~~~~~~~~~~