feature symfony#53123 [VarDumper] Added default message for dd function (Shamimul Alam)

This PR was squashed before being merged into the 7.1 branch.

Discussion
----------

[VarDumper] Added default message for dd function

| Q             | A
| ------------- | ---
| Branch?       | 7.1
| Bug fix?      | no
| New feature?  | yes
| Deprecations? | no
| Issues        |
| License       | MIT

This will facilitate writing empty dd() statements during unorthodox debugging in the code. It will be helpful for both novice and experienced developers.

Commits
-------

857db8f [VarDumper] Added default message for dd function

Author: fabpot

src/Symfony/Component/VarDumper/Resources/functions/dump.php

@@ -49,6 +49,12 @@ function dd(mixed ...$vars): never
             header('HTTP/1.1 500 Internal Server Error');
         }
 
+        if (!$vars) {
+            VarDumper::dump(new ScalarStub('🐛'));
+
+            exit(1);
+        }
+
         if (array_key_exists(0, $vars) && 1 === count($vars)) {
             VarDumper::dump($vars[0]);
         } else {