fix tox error

Change-Id: I62ac0a3e406829f303e88e6e4aa259a5a08415f1

tox.ini

@@ -13,7 +13,7 @@ install_command = pip install -U {opts} {packages}
 setenv =
     VIRTUAL_ENV={envdir}
 deps =
-    -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/master}
     -r{toxinidir}/requirements.txt
     -r{toxinidir}/test-requirements.txt
     Mako>=0.4.0,<1.3.0
@@ -24,6 +24,7 @@ passenv =
     no_proxy
 
 [testenv:venv]
+usedevelop = False
 basepython = python3
 commands = {posargs}
 passenv = OS_*