git subrepo pull (merge) mailcow/src/mailcow-dockerized

Among other things, this updates Dovecot to 2.3.13, which is a
critical security update.

subrepo: subdir:   "mailcow/src/mailcow-dockerized"
  merged:   "376574d9"
upstream: origin:   "https://github.com/mailcow/mailcow-dockerized.git"
  branch:   "master"
  commit:   "6f14955b"
git-subrepo: version:  "0.4.3"
  origin:   "???"
  commit:   "???"
Change-Id: Idf4859ddaaebf6997afbb0cebffc8bf3f5b902a0
diff --git a/mailcow/src/mailcow-dockerized/data/web/inc/lib/vendor/composer/ClassLoader.php b/mailcow/src/mailcow-dockerized/data/web/inc/lib/vendor/composer/ClassLoader.php
index fce8549..1a58957 100644
--- a/mailcow/src/mailcow-dockerized/data/web/inc/lib/vendor/composer/ClassLoader.php
+++ b/mailcow/src/mailcow-dockerized/data/web/inc/lib/vendor/composer/ClassLoader.php
@@ -37,8 +37,8 @@
  *
  * @author Fabien Potencier <fabien@symfony.com>
  * @author Jordi Boggiano <j.boggiano@seld.be>
- * @see    http://www.php-fig.org/psr/psr-0/
- * @see    http://www.php-fig.org/psr/psr-4/
+ * @see    https://www.php-fig.org/psr/psr-0/
+ * @see    https://www.php-fig.org/psr/psr-4/
  */
 class ClassLoader
 {
@@ -60,7 +60,7 @@
     public function getPrefixes()
     {
         if (!empty($this->prefixesPsr0)) {
-            return call_user_func_array('array_merge', $this->prefixesPsr0);
+            return call_user_func_array('array_merge', array_values($this->prefixesPsr0));
         }
 
         return array();