minor symfony#12558 Note doctrine bundle version for middlewares (Steveb-p)

This PR was merged into the 4.3 branch.

Discussion
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Note doctrine bundle version for middlewares

Adds note regarding Doctrine middlewares being available since version 1.11 of the bundle

See: doctrine/DoctrineBundle#956

Commits
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afacf4c Note doctrine bundle version for middlewares

Author: javiereguiluz

messenger.rst

@@ -1363,6 +1363,10 @@ middleware and *only* include your own:
 Middleware for Doctrine
 ~~~~~~~~~~~~~~~~~~~~~~~
 
+.. note::
+
+    Doctrine middlewares mentioned below require `doctrine/doctrine-bundle@^1.11`.
+
 If you use Doctrine in your app, a number of optional middleware exist that you
 may want to use: