fix: Downgrade to PHP 7.3

Author: Nattfarinn

eZ/Publish/Core/Persistence/Legacy/Content/Handler.php

@@ -85,7 +85,10 @@ class Handler implements BaseContentHandler
      */
     protected $treeHandler;
 
-    protected LanguageHandler $languageHandler;
+    /**
+     * @var \eZ\Publish\SPI\Persistence\Content\Language\Handler
+     */
+    protected $languageHandler;
 
     /** @var \Psr\Log\LoggerInterface */
     private $logger;

eZ/Publish/Core/Persistence/Legacy/Tests/Content/ContentHandlerTest.php

@@ -109,7 +109,10 @@ class ContentHandlerTest extends TestCase
      */
     protected $contentTypeHandlerMock;
 
-    protected LanguageHandler $languageHandlerMock;
+    /**
+     * @var \eZ\Publish\Core\Persistence\Legacy\Content\Language\Handler
+     */
+    protected $languageHandlerMock;
 
     /**
      * @covers \eZ\Publish\Core\Persistence\Legacy\Content\Handler::create