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

Extension/Core/Type/ChoiceType.php

@@ -160,7 +160,7 @@ public function finishView(FormView $view, FormInterface $form, array $options)
      */
     public function setDefaultOptions(OptionsResolverInterface $resolver)
     {
-        $choiceListCache = & $this->choiceListCache;
+        $choiceListCache = &$this->choiceListCache;
 
         $choiceList = function (Options $options) use (&$choiceListCache) {
             // Harden against NULL values (like in EntityType and ModelType)