Add /media/plg_system_compat to exceptions

Author: richard67

build/deleted_file_check.php

@@ -106,6 +106,7 @@ function usage($command)
     'images/sampledata',
     'installation',
     'media/plg_quickicon_eos310',
+    'media/plg_system_compat',
     'media/system/images',
     'modules/mod_search',
     'plugins/fields/repeatable',