minor #33523 Fix lint commands frozen on empty stdin (chalasr)

This PR was merged into the 4.4 branch.

Discussion
----------

Fix lint commands frozen on empty stdin

| Q             | A
| ------------- | ---
| Branch?       | 4.4
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

Running e.g. `lint:yaml -` with no piped content makes the command hangs currently, this makes it fail instead. Also fixes the command help which we forgot to update

Commits
-------

b60e0c1454 Fix lint commands frozen on empty stdin

Author: nicolas-grekas

Tests/Command/XliffLintCommandTest.php

@@ -35,29 +35,12 @@ public function testGetHelp()
     {
         $command = new XliffLintCommand();
         $expected = <<<EOF
-The <info>%command.name%</info> command lints a XLIFF file and outputs to STDOUT
-the first encountered syntax error.
-
-You can validates XLIFF contents passed from STDIN:
-
-  <info>cat filename | php %command.full_name%</info>
-
-You can also validate the syntax of a file:
-
-  <info>php %command.full_name% filename</info>
-
-Or of a whole directory:
-
-  <info>php %command.full_name% dirname</info>
-  <info>php %command.full_name% dirname --format=json</info>
-
 Or find all files in a bundle:
 
   <info>php %command.full_name% @AcmeDemoBundle</info>
-
 EOF;
 
-        $this->assertEquals($expected, $command->getHelp());
+        $this->assertStringContainsString($expected, $command->getHelp());
     }
 
     public function testLintFilesFromBundleDirectory()

Tests/Command/YamlLintCommandTest.php

@@ -72,29 +72,12 @@ public function testGetHelp()
     {
         $command = new YamlLintCommand();
         $expected = <<<EOF
-The <info>%command.name%</info> command lints a YAML file and outputs to STDOUT
-the first encountered syntax error.
-
-You can validates YAML contents passed from STDIN:
-
-  <info>cat filename | php %command.full_name%</info>
-
-You can also validate the syntax of a file:
-
-  <info>php %command.full_name% filename</info>
-
-Or of a whole directory:
-
-  <info>php %command.full_name% dirname</info>
-  <info>php %command.full_name% dirname --format=json</info>
-
 Or find all files in a bundle:
 
   <info>php %command.full_name% @AcmeDemoBundle</info>
-
 EOF;
 
-        $this->assertEquals($expected, $command->getHelp());
+        $this->assertStringContainsString($expected, $command->getHelp());
     }
 
     public function testLintFilesFromBundleDirectory()