minor #35731 [Routing] marked configurators traits as internal (HeahDude)

This PR was merged into the 5.1-dev branch.

Discussion
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[Routing] marked configurators traits as internal

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| Deprecations? | no <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tickets       | Fix https://github.com/symfony/symfony/pull/30501#discussion_r376806342 <!-- prefix each issue number with "Fix #", if any -->
| License       | MIT
| Doc PR        | not needed
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Commits
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52efec76ad [Routing] marked configurators traits as internal

src/Symfony/Component/Routing/Loader/Configurator/Traits/LocalizedRouteTrait.php

@@ -15,6 +15,8 @@ use Symfony\Component\Routing\Route;
 use Symfony\Component\Routing\RouteCollection;
 
 /**
+ * @internal
+ *
  * @author Nicolas Grekas <p@tchwork.com>
  * @author Jules Pietri <jules@heahprod.com>
  */

src/Symfony/Component/Routing/Loader/Configurator/Traits/PrefixTrait.php

@@ -15,6 +15,8 @@ use Symfony\Component\Routing\Route;
 use Symfony\Component\Routing\RouteCollection;
 
 /**
+ * @internal
+ *
  * @author Nicolas Grekas <p@tchwork.com>
  */
 trait PrefixTrait