Support service closure shorthand syntax in YamlFileLoader

Postponing until this is available in a supported symfony version.

Hardly needs to be postponed, Drupal has a copy of YamlFileLoader, the patch could be applied any time.

Documentation is underway too.

Yeah we can still do this, no need to wait years.

https://symfony.com/releases/7.3 comes out in May

https://www.drupal.org/about/core/policies/core-release-cycles/schedule → 11.2 comes out in Jun

if this gets in now, a released Symfony still will predated a released Drupal

(not that I have any idea why would that be a prerequisite)

FWIW we have symfony 7.3 in core now

Rebased, fixed the phpstan issues, added test coverage

Updated the issue summary and added a change record.

Ran test only job here https://git.drupalcode.org/issue/drupal-3498038/-/jobs/5941301

1) Drupal\Tests\Core\DependencyInjection\YamlFileLoaderTest::testParseDefinitionsWithProvider
Symfony\Component\DependencyInjection\Exception\ServiceNotFoundException: The service "example_service_closure_shorthand" has a dependency on a non-existent service ">example_service_1". Did you mean one of these: "example_service_1", "example_service_2"?
/builds/issue/drupal-3498038/vendor/symfony/dependency-injection/Compiler/CheckExceptionOnInvalidReferenceBehaviorPass.php:116
/builds/issue/drupal-3498038/vendor/symfony/dependency-injection/Compiler/CheckExceptionOnInvalidReferenceBehaviorPass.php:123
/builds/issue/drupal-3498038/vendor/symfony/dependency-injection/Compiler/CheckExceptionOnInvalidReferenceBehaviorPass.php:83
/builds/issue/drupal-3498038/vendor/symfony/dependency-injection/Compiler/AbstractRecursivePass.php:84
/builds/issue/drupal-3498038/vendor/symfony/dependency-injection/Compiler/CheckExceptionOnInvalidReferenceBehaviorPass.php:48
/builds/issue/drupal-3498038/vendor/symfony/dependency-injection/Compiler/AbstractRecursivePass.php:93
/builds/issue/drupal-3498038/vendor/symfony/dependency-injection/Compiler/CheckExceptionOnInvalidReferenceBehaviorPass.php:48
/builds/issue/drupal-3498038/vendor/symfony/dependency-injection/Compiler/AbstractRecursivePass.php:84
/builds/issue/drupal-3498038/vendor/symfony/dependency-injection/Compiler/CheckExceptionOnInvalidReferenceBehaviorPass.php:48
/builds/issue/drupal-3498038/vendor/symfony/dependency-injection/Compiler/AbstractRecursivePass.php:45
/builds/issue/drupal-3498038/vendor/symfony/dependency-injection/Compiler/CheckExceptionOnInvalidReferenceBehaviorPass.php:39
/builds/issue/drupal-3498038/vendor/symfony/dependency-injection/Compiler/Compiler.php:73
/builds/issue/drupal-3498038/vendor/symfony/dependency-injection/ContainerBuilder.php:813
/builds/issue/drupal-3498038/core/tests/Drupal/Tests/Core/DependencyInjection/YamlFileLoaderTest.php

Change makes sense and CR is clear.

Don't see any open threads so LGTM