minor #13317 Kernel constructor (SF v4.4.5) accepts only 2 args (thePanz)

This PR was merged into the 4.4 branch.

Discussion
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Kernel constructor (SF v4.4.5) accepts only 2 args

In v4.4.5 the Kernel constructor only accepts 2 arguments.
Legacy-Migration documentation updated accordingly

Commits
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391d469 Kernel constructor (SF v4.4.5) accepts only 2 args

Author: javiereguiluz

migration.rst

@@ -268,7 +268,7 @@ could look something like this::
         Request::setTrustedHosts([$trustedHosts]);
     }
 
-    $kernel = new Kernel($_SERVER['APP_ENV'], (bool) $_SERVER['APP_DEBUG'], dirname(__DIR__));
+    $kernel = new Kernel($_SERVER['APP_ENV'], (bool) $_SERVER['APP_DEBUG']);
     $request = Request::createFromGlobals();
     $response = $kernel->handle($request);