Fixed a small spelling mistake

Fixed a small typo.

Change-Id: Id52e08067911ef7c6aff49f5c78d7d970fa77d2a
diff --git a/tempest/cmd/verify_tempest_config.py b/tempest/cmd/verify_tempest_config.py
index a7e0ee3..65a3a95 100755
--- a/tempest/cmd/verify_tempest_config.py
+++ b/tempest/cmd/verify_tempest_config.py
@@ -335,7 +335,7 @@
             continue
         results = verify_extensions(os, service, results)
 
-    # Verify API verisons of all services in the keystone catalog and keystone
+    # Verify API versions of all services in the keystone catalog and keystone
     # itself.
     services.append('keystone')
     for service in services: