Merge branch '5.3' into 5.4

* 5.3:
  [HttpClient] fix RetryableHttpClient when a response is canceled
  [Uid] fix 4 missing bits of entropy in UUIDv4
  [Runtime] Drop class validation of composer "extra.runtime.class"

Author: nicolas-grekas

Internal/ComposerPlugin.php

@@ -18,7 +18,6 @@
 use Composer\Plugin\PluginInterface;
 use Composer\Script\ScriptEvents;
 use Symfony\Component\Filesystem\Filesystem;
-use Symfony\Component\Runtime\RuntimeInterface;
 use Symfony\Component\Runtime\SymfonyRuntime;
 
 /**
@@ -98,10 +97,6 @@ public function updateAutoloadFile(): void
 
         $runtimeClass = $extra['class'] ?? SymfonyRuntime::class;
 
-        if (SymfonyRuntime::class !== $runtimeClass && !is_subclass_of($runtimeClass, RuntimeInterface::class)) {
-            throw new \InvalidArgumentException(sprintf('Class "%s" listed under "extra.runtime.class" in your composer.json file '.(class_exists($runtimeClass) ? 'should implement "%s".' : 'not found.'), $runtimeClass, RuntimeInterface::class));
-        }
-
         unset($extra['class'], $extra['autoload_template']);
 
         $code = strtr(file_get_contents($autoloadTemplate), [