minor #9327 Fixed a versionadded directive (javiereguiluz)

This PR was merged into the 3.4 branch.

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Fixed a versionadded directive

Spotted while reviewing #9325.

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6be33f6 Fixed a versionadded directive

Author: javiereguiluz

components/translation/usage.rst

@@ -436,7 +436,7 @@ The ``$messages`` variable will have the following structure::
 Adding Notes to Translation Contents
 ------------------------------------
 
-.. versionadded: 3.4
+.. versionadded:: 3.4
     The feature to load and dump translation notes was introduced in Symfony 3.4.
 
 Sometimes translators need additional context to better decide how to translate