Move v3 identity endpoint group tests to work w/ pre-prov

I don't see any limitations by using pre-provisioned
credentials for these tests:

* test_create_list_show_check_delete_endpoint_group
* test_update_endpoint_group

Note that these tests aren't interop tests [0] so can
be safely moved.

[0] http://codesearch.openstack.org/?q=admin.v3.test_endpoint_groups&i=nope&files=&repos=interop

Change-Id: I2638348989ecdda14a88b0f8817ff42a1a6c9e77
diff --git a/tempest/api/identity/admin/v3/test_endpoint_groups.py b/tempest/api/identity/admin/v3/test_endpoint_groups.py
index eef93c2..625568d 100644
--- a/tempest/api/identity/admin/v3/test_endpoint_groups.py
+++ b/tempest/api/identity/admin/v3/test_endpoint_groups.py
@@ -20,6 +20,10 @@
 
 
 class EndPointGroupsTest(base.BaseIdentityV3AdminTest):
+    # NOTE: force_tenant_isolation is true in the base class by default but
+    # overridden to false here to allow test execution for clouds using the
+    # pre-provisioned credentials provider.
+    force_tenant_isolation = False
 
     @classmethod
     def setup_clients(cls):