Enable Sahara API health check

This patch enables health check execution in sahara_api container.

Change-Id: Ic14d9c5b9a4ad014181e8505fae3d2f656b7b0bd
Depends-On: Ie724b155fa071da9f1baee193cf79e2ecdc2ff30

docker/services/sahara-api.yaml

@@ -129,6 +129,8 @@ outputs:
             net: host
             privileged: false
             restart: always
+            healthcheck:
+              test: /openstack/healthcheck
             volumes:
               list_concat:
                 - {get_attr: [ContainersCommon, volumes]}