minor #30233 [Twig] removed usage of non-namespaced classes (fabpot)

This PR was merged into the 3.4 branch.

Discussion
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[Twig] removed usage of non-namespaced classes

| Q             | A
| ------------- | ---
| Branch?       | 3.4
| Bug fix?      | no
| New feature?  | no <!-- don't forget to update src/**/CHANGELOG.md files -->
| BC breaks?    | no     <!-- see https://symfony.com/bc -->
| Deprecations? | no <!-- don't forget to update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tests pass?   | yes    <!-- please add some, will be required by reviewers -->
| Fixed tickets | n/a
| License       | MIT
| Doc PR        | n/a

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Commits
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bd719cd7e1 [Twig] removed usage of non-namespaced classes

Author: fabpot

DataCollector/TwigDataCollector.php

@@ -16,6 +16,7 @@
 use Symfony\Component\HttpKernel\DataCollector\DataCollector;
 use Symfony\Component\HttpKernel\DataCollector\LateDataCollectorInterface;
 use Twig\Environment;
+use Twig\Error\LoaderError;
 use Twig\Markup;
 use Twig\Profiler\Dumper\HtmlDumper;
 use Twig\Profiler\Profile;
@@ -70,7 +71,7 @@ public function lateCollect()
             if ($profile->isTemplate()) {
                 try {
                     $template = $this->twig->load($name = $profile->getName());
-                } catch (\Twig_Error_Loader $e) {
+                } catch (LoaderError $e) {
                     $template = null;
                 }