minor #14573 [Console] Caution about disabling auto exit flag (ybenhssaien)

This PR was submitted for the 5.1 branch but it was squashed and merged into the 4.4 branch instead.

Discussion
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[Console] Caution about disabling auto exit flag

Like mentionned in the class comment : https://github.com/symfony/symfony/blob/5.1/src/Symfony/Component/Console/Tester/ApplicationTester.php#L23 : the auto exist flag should be disabled, otherwise the tests won't run

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Commits
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b28603e [Console] Caution about disabling auto exit flag

Author: xabbuh

console.rst

@@ -393,6 +393,16 @@ console::
     not dispatched. If you need to test those events, use the
     :class:`Symfony\\Component\\Console\\Tester\\ApplicationTester` instead.
 
+.. caution::
+
+    When testing commands using the :class:`Symfony\\Component\\Console\\Tester\\ApplicationTester`
+    class, don't forget to disable the auto exit flag::
+
+        $application = new Application();
+        $application->setAutoExit(false);
+        
+        $tester = new ApplicationTester($application);
+
 .. note::
 
     When using the Console component in a standalone project, use