Move export public calendar additional feature to core

mod/cal.php

@@ -292,13 +292,6 @@ function cal_content(App $a)
 			return;
 		}
 
-		// Test permissions
-		// Respect the export feature setting for all other /cal pages if it's not the own profile
-		if ((local_user() !== $owner_uid) && !Feature::isEnabled($owner_uid, "export_calendar")) {
-			notice(DI::l10n()->t('Permission denied.') . EOL);
-			DI::baseUrl()->redirect('cal/' . $nick);
-		}
-
 		// Get the export data by uid
 		$evexport = Event::exportListByUserId($owner_uid, $format);