[TASK] Move TCA instructions out of ext_tables if they do not belong there

Configuration/TCA/Overrides/sys_template.php

+<?php
+
+\TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addStaticFile(
+	'sg_youtube',
+	'Configuration/TypoScript',
+	'SG Youtube'
+);

Configuration/TCA/Overrides/tt_content.php

@@ -4,3 +4,9 @@ $GLOBALS['TCA']['tt_content']['types']['list']['subtypes_addlist']['sgyoutube_yo
 \TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addPiFlexFormValue(
 	'sgyoutube_youtube', 'FILE:EXT:sg_youtube/Configuration/FlexForms/flexform_sgyoutube_youtube.xml'
 );
+
+\TYPO3\CMS\Extbase\Utility\ExtensionUtility::registerPlugin(
+	'SGalinski.sg_youtube',
+	'Youtube',
+	'YouTube Videos'
+);

ext_tables.php

-<?php
-if (!defined('TYPO3_MODE')) {
-	die('Access denied.');
-}
-
-\TYPO3\CMS\Extbase\Utility\ExtensionUtility::registerPlugin(
-	'SGalinski.sg_youtube',
-	'Youtube',
-	'YouTube Videos'
-);
-
-\TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addStaticFile('sg_youtube', 'Configuration/TypoScript', 'SG Youtube');