minor #14090 CS: Unary operators should be placed adjacent to their operands (keradus)

This PR was merged into the 2.3 branch.

Discussion
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CS: Unary operators should be placed adjacent to their operands

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

Update before upcoming changes on PHP CS Fixer 1.7

To keep fabbot.io happy ;)

Commits
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2367f4a CS: Unary operators should be placed adjacent to their operands

Author: fabpot

Loader/ArrayLoader.php

@@ -53,7 +53,7 @@ public function load($resource, $locale, $domain = 'messages')
     private function flatten(array &$messages, array $subnode = null, $path = null)
     {
         if (null === $subnode) {
-            $subnode = & $messages;
+            $subnode = &$messages;
         }
         foreach ($subnode as $key => $value) {
             if (is_array($value)) {