Move shebang

Change-Id: I13f7de98775ac837cc348ed0ae21403d88f57349
diff --git a/roles/create-lxd/library/host_dns_check.py b/roles/create-lxd/library/host_dns_check.py
index d69727d..c8b3e17 100755
--- a/roles/create-lxd/library/host_dns_check.py
+++ b/roles/create-lxd/library/host_dns_check.py
@@ -1,3 +1,4 @@
+#!/usr/bin/env python
 
 # Copyright 2017-present Open Networking Foundation
 #
@@ -13,9 +14,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-
-#!/usr/bin/env python
-
 import sys
 import json
 import shlex