minor #10092 [Messenger] Transport not mandatory (kunicmarko20, javiereguiluz)

This PR was merged into the 4.1 branch.

Discussion
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[Messenger] Transport not mandatory

After reading the documentation a few days ago I thought that async is the only way this library works, after seeing the discussion today in #general on slack, @sroze explained it. Hopefully, this will help others if they find themselves in the same problem.

Commits
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47e275b Reword
f0942d2 Reword
bdbe542 Transport not mandatory

Author: javiereguiluz

messenger.rst

@@ -100,9 +100,11 @@ Once you've created your handler, you need to register it:
 Transports
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-The communication with queuing systems or third parties is delegated to
-libraries for now. The built-in AMQP transport allows you to communicate with
-most of the AMQP brokers such as RabbitMQ.
+By default, messages are processed as soon as they are dispatched. If you prefer
+to process messages asynchronously, you must configure a transport. These
+transports communicate with your application via queuing systems or third parties.
+The built-in AMQP transport allows you to communicate with most of the AMQP
+brokers such as RabbitMQ.
 
 .. note::