feature #15479 [Console] Document CommandTester::assertCommandIsSuccessful() usage (yoannrenard)

This PR was merged into the 5.4 branch.

Discussion
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[Console] Document CommandTester::assertCommandIsSuccessful() usage

This PR documents how to use the new CommandTester::assertCommandIsSuccessful() method.

Commits
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aad93f4 [Console] Document CommandTester::assertCommandIsSuccessful() usage

Author: OskarStark

console.rst

@@ -384,6 +384,8 @@ console::
                 // e.g: '--some-option' => 'option_value',
             ]);
 
+            $commandTester->assertCommandIsSuccessful();
+
             // the output of the command in the console
             $output = $commandTester->getDisplay();
             $this->assertStringContainsString('Username: Wouter', $output);
@@ -400,6 +402,10 @@ call ``setAutoExit(false)`` on it to get the command result in ``CommandTester``
     The ``setAutoExit()`` method for single-command applications was introduced
     in Symfony 5.2.
 
+.. versionadded:: 5.4
+
+    The ``assertCommandIsSuccessful()`` method was introduced in Symfony 5.4.
+
 .. tip::
 
     You can also test a whole console application by using