message: fix vm creation with no security group
diff: @@ -113,6 +113,9 @@ export class SecurityGroupService extends BaseBackendService<SecurityGroup> {
  .switchMap((securityGroup: SecurityGroup) => {
  sg = securityGroup;
  + if (!ingressRules.length && !egressRules.length) {
  + return Observable.of(null);
  + }
  const addRuleRequests = [];
  const addRule = (type, rule) => {
  const r = new NetworkRule(Object.assign({}, rule));
  