fix: ensure that attributemap actually gets applied

Merge branch 'master' of https://github.com/privacyidea/simplesamlphp-module-privacyidea

lib/Auth/Source/PrivacyideaAuthSource.php

@@ -45,13 +45,13 @@ class PrivacyideaAuthSource extends UserPassBase
 
         parent::__construct($info, $config);
 
-        if (!in_array('attributemap', $config, true)) {
+        if (!array_key_exists('attributemap', $config)) {
             $config['attributemap'] = [];
         }
-        if (!in_array('detailmap', $config, true)) {
+        if (!array_key_exists('detailmap', $config)) {
             $config['detailmap'] = [];
         }
-        if (!in_array('concatenationmap', $config, true)) {
+        if (!array_key_exists('concatenationmap', $config)) {
             $config['concatenationmap'] = [];
         }