Run openssh state after compute added to add host fingerprints

Since 2019.2.6 hosts fingerprints are managed by OpenSSH state, so
run this state to add host fingerprints after compute node is added.

Change-Id: I1ba3c6af3dcd6046bfa370f9889293ef34a97657
Related-Prod: PROD-32054
diff --git a/openstack-compute-install.groovy b/openstack-compute-install.groovy
index 8e483cb..c4db64b 100644
--- a/openstack-compute-install.groovy
+++ b/openstack-compute-install.groovy
@@ -105,9 +105,10 @@
                 }
             }
 
-            // host records for compute nodes are generated dynamically - so apply state after node setup
-            stage('Update Hosts file') {
-                salt.enforceState(pepperEnv, "I@linux:system", 'linux.network.host', true, true, batch_size)
+            // host records and fingerprints for compute nodes are generated dynamically - so apply state after node setup
+            stage('Update Hosts file and fingerprints') {
+                salt.enforceState(pepperEnv, "I@linux:network:host", 'linux.network.host', true, true, batch_size)
+                salt.enforceState(pepperEnv, "I@linux:system", 'openssh', true, true, batch_size)
             }
 
             // discover added compute hosts