Update TOX_CONSTRAINTS_FILE for stable/ussuri

Update the URL to the upper-constraints file to point to the redirect
rule on releases.openstack.org so that anyone working on this branch
will switch to the correct upper-constraints list automatically when
the requirements repository branches.

Until the requirements repository has as stable/ussuri branch, tests will
continue to use the upper-constraints list on master.

Change-Id: I551ed7ae50976a846b20a4ee929c066c35125d5c

1 files changed, 1 insertions, 1 deletions

diff --git a/tox.ini b/tox.ini
index 13f5317b..a77d374a 100644
--- a/tox.ini
+++ b/tox.ini
@@ -7,7 +7,7 @@ envlist = py{36,37},pep8
 basepython = python3
 deps = -r{toxinidir}/test-requirements.txt
        -r{toxinidir}/requirements.txt
-       -c{env:UPPER_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.txt}
+       -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/ussuri}
 install_command = pip install {opts} {packages}
 usedevelop = True
 setenv = VIRTUAL_ENV={envdir}