minor #11678 Blank line after directive and no blank line after filepath (OskarStark)

This PR was merged into the 4.3 branch.

Discussion
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Blank line after directive and no blank line after filepath

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Commits
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dd896ae Blank line after directive and no blank line after filepath

Author: wouterj

mailer.rst

@@ -2,6 +2,7 @@ Sending Emails with Mailer
 ==========================
 
 .. versionadded:: 4.3
+
     The Mailer component was added in Symfony 4.3 and is currently experimental.
     The previous solution - Swift Mailer - is still valid: :doc:`Swift Mailer</email>`.
 
@@ -62,7 +63,6 @@ You'll now have a new line in your ``.env`` file that you can uncomment:
 .. code-block:: bash
 
     # .env
-
     SENDGRID_KEY=
     MAILER_DSN=smtp://$SENDGRID_KEY@sendgrid
 

messenger.rst

@@ -947,6 +947,7 @@ Serializing Messages
 ~~~~~~~~~~~~~~~~~~~~
 
 .. versionadded:: 4.3
+
     The default serializer changed in 4.3 from the Symfony serializer to the
     native PHP serializer. Existing applications should configure their transports
     to use the Symfony serializer to avoid losing already-queued messages after