certprofile plugin: Use binary mode for file with binary data

Part of the work for: https://fedorahosted.org/freeipa/ticket/4985

Reviewed-By: Martin Basti <mbasti@redhat.com>
Reviewed-By: Petr Spacek <pspacek@redhat.com>

ipalib/plugins/certprofile.py

@@ -224,7 +224,7 @@ class certprofile_show(LDAPRetrieve):
 
         result = super(certprofile_show, self).forward(*keys, **options)
         if 'out' in options and 'config' in result['result']:
-            with open(options['out'], 'w') as f:
+            with open(options['out'], 'wb') as f:
                 f.write(result['result'].pop('config'))
             result['summary'] = (
                 _("Profile configuration stored in file '%(file)s'")