make the rand_name value shorter

Avoids out of range errors with postgresql as the default backend. PostgreSQL ids which have an integer type of 4 bytes would trigger this exception for tests which use rand_name on id columns.

Fixes bug 1056229

Change-Id: Ic8286fe9320e80c2e8a9ec9f8857b5d1f304660f
diff --git a/tempest/common/utils/data_utils.py b/tempest/common/utils/data_utils.py
index 752bc10..fc7c112 100644
--- a/tempest/common/utils/data_utils.py
+++ b/tempest/common/utils/data_utils.py
@@ -5,7 +5,7 @@
 
 
 def rand_name(name='test'):
-    return name + str(random.randint(1, 99999999999))
+    return name + str(random.randint(1, 999999))
 
 
 def build_url(host, port, api_version=None, path=None,