minor #13866 [2.3] Remove most refs uses (nicolas-grekas)

This PR was merged into the 2.3 branch.

Discussion
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[2.3] Remove most refs uses

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #13813
| License       | MIT
| Doc PR        | -

Removes some references usages. They are error prone, and trigger too many copies-on-writes.

Commits
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8862705 [2.3] Remove most refs uses

Author: fabpot

ContainerBuilder.php

@@ -997,9 +997,7 @@ public function createService(Definition $definition, $id, $tryProxy = true)
     public function resolveServices($value)
     {
         if (is_array($value)) {
-            foreach ($value as &$v) {
-                $v = $this->resolveServices($v);
-            }
+            $value = array_map(array($this, 'resolveServices'), $value);
         } elseif ($value instanceof Reference) {
             $value = $this->get((string) $value, $value->getInvalidBehavior());
         } elseif ($value instanceof Definition) {