[TASK] Cleanup ext_localconf.php (#833)

After dropping TYPO3 10.4 support:

- Using an anonymous function is not needed anymore
- declare(strict_types=1); can and should be used
- Use statements instead of FQCN should be used

resolves https://github.com/TYPO3-Documentation/tea/issues/826

---------

Co-authored-by: Chris Müller <2566282+brotkrueml@users.noreply.github.com>

ext_localconf.php

@@ -1,31 +1,34 @@
 <?php
 
+declare(strict_types=1);
+
+use TTN\Tea\Controller\TeaController;
+use TYPO3\CMS\Extbase\Utility\ExtensionUtility;
+
 defined('TYPO3') or die('Access denied.');
 
-(static function (): void {
 // This makes the plugin available for front-end rendering.
-    \TYPO3\CMS\Extbase\Utility\ExtensionUtility::configurePlugin(
+ExtensionUtility::configurePlugin(
     // extension name, matching the PHP namespaces (but without the vendor)
     'Tea',
     // arbitrary, but unique plugin name (not visible in the BE)
     'TeaIndex',
     // all actions
     [
-            \TTN\Tea\Controller\TeaController::class => 'index',
+        TeaController::class => 'index',
     ],
     // non-cacheable actions
     [
-            \TTN\Tea\Controller\TeaController::class => '',
+        TeaController::class => '',
     ]
 );
-    \TYPO3\CMS\Extbase\Utility\ExtensionUtility::configurePlugin(
+ExtensionUtility::configurePlugin(
     'Tea',
     'TeaShow',
     [
-            \TTN\Tea\Controller\TeaController::class => 'show',
+        TeaController::class => 'show',
     ],
     [
-            \TTN\Tea\Controller\TeaController::class => '',
+        TeaController::class => '',
     ]
 );
-})();