Fix create_server_snapshot for microversion

Location returned till microversion 2.44
image_id returned from microversion 2.45

Added support in manager for both

Change-Id: I5ef9233d9ba2437198bac1357782a9639024dc79
diff --git a/tempest/scenario/manager.py b/tempest/scenario/manager.py
index 73ce08f..2843498 100644
--- a/tempest/scenario/manager.py
+++ b/tempest/scenario/manager.py
@@ -815,7 +815,9 @@
             name = data_utils.rand_name(self.__class__.__name__ + 'snapshot')
         LOG.debug("Creating a snapshot image for server: %s", server['name'])
         image = _images_client.create_image(server['id'], name=name, **kwargs)
-        image_id = image.response['location'].split('images/')[1]
+        # microversion 2.45 and above returns image_id
+        image_id = image.get('image_id') or image.response['location'].split(
+            'images/')[1]
         waiters.wait_for_image_status(_image_client, image_id, 'active')
 
         self.addCleanup(_image_client.wait_for_resource_deletion,