Use victoria stable constraint in tox to release 26.0.0

We are going to release Tempest new tag 26.0.0 to declare
the end of support for stable/stein. So that new tag use
stable/victoria constraint in the tox env as victoria constraints
for sure will work with tag. It did not use wallaby constraints
as wallaby dev cycle is in progress and so does their constraints.

Further information:
 https://docs.openstack.org/tempest/latest/requirement_upper_constraint_for_tempest.html

Change-Id: I31433c15984e38e5651b2f3d10c8769f59e30cc1
diff --git a/tox.ini b/tox.ini
index d8e059a..80d5de2 100644
--- a/tox.ini
+++ b/tox.ini
@@ -11,7 +11,7 @@
     VIRTUAL_ENV={envdir}
     OS_TEST_PATH=./tempest/test_discover
 deps =
-    -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+    -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/victoria}
     -r{toxinidir}/requirements.txt
 
 [testenv]
@@ -28,7 +28,7 @@
 install_command = pip install {opts} {packages}
 whitelist_externals = *
 deps =
-    -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+    -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/victoria}
     -r{toxinidir}/requirements.txt
     -r{toxinidir}/test-requirements.txt
 commands =
@@ -263,7 +263,7 @@
 
 [testenv:venv]
 deps =
-  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/victoria}
   -r{toxinidir}/requirements.txt
   -r{toxinidir}/doc/requirements.txt
 commands = {posargs}
@@ -278,7 +278,7 @@
 
 [testenv:docs]
 deps =
-  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/victoria}
   -r{toxinidir}/doc/requirements.txt
 commands =
   sphinx-apidoc -f -o doc/source/tests/compute tempest/api/compute
@@ -363,7 +363,7 @@
 
 [testenv:releasenotes]
 deps =
-  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/victoria}
   -r{toxinidir}/doc/requirements.txt
 commands =
   rm -rf releasenotes/build