Server Upgrade: Handle connection better in updates_from_dict

Connection should be closed if update is done

https://fedorahosted.org/freeipa/ticket/4904

Reviewed-By: David Kupka <dkupka@redhat.com>

ipaserver/install/ldapupdate.py

@@ -868,10 +868,11 @@ class LDAPUpdate:
         updates is a dictionary containing the updates
         """
         self.modified = False
-        if not self.conn:
+        try:
             self.create_connection()
-
-        self._run_updates(updates)
+            self._run_updates(updates)
+        finally:
+            self.close_connection()
 
         return self.modified