minor #20604 [Messenger] Describe --keepalive option (AmazonSQS & Beanstalkd) (OskarStark)

This PR was squashed before being merged into the 7.2 branch.

Discussion
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[Messenger] Describe `--keepalive` option (AmazonSQS & Beanstalkd)

Follows
* symfony/symfony#53508

Fixes #20305 #20381

cc `@HypeMC` `@chalasr`

Commits
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8ce8f9b [Messenger] Describe `--keepalive` option (AmazonSQS & Beanstalkd)

Author: javiereguiluz

messenger.rst

@@ -543,6 +543,19 @@ command with the ``--all`` option:
 
     The ``--all`` option was introduced in Symfony 7.1.
 
+The ``--keepalive`` option can be used to prevent messages from being prematurely
+redelivered during long-running processing. It marks the message as "in progress"
+and prevents it from being redelivered until the worker finishes processing it.
+
+.. note::
+
+    This option is only available for supported transports, which are
+    the Beanstalkd and AmazonSQS transports.
+
+.. versionadded:: 7.2
+
+    The ``--keepalive`` option was introduced in Symfony 7.2.
+
 .. tip::
 
     In a development environment and if you're using the Symfony CLI tool,
@@ -1709,6 +1722,10 @@ The transport has a number of options:
     The message time to run before it is put back in the ready queue - in
     seconds.
 
+.. versionadded:: 7.2
+
+    Keepalive support, using the ``--keepalive`` option, was added in Symfony 7.2.
+
 .. _messenger-redis-transport:
 
 Redis Transport
@@ -2031,6 +2048,10 @@ The transport has a number of options:
     FIFO queues don't support setting a delay per message, a value of ``delay: 0``
     is required in the retry strategy settings.
 
+.. versionadded:: 7.2
+
+    Keepalive support, using the `--keepalive` option, was added in Symfony 7.2.
+
 Serializing Messages
 ~~~~~~~~~~~~~~~~~~~~