Use stable constraint in tox to release new tag for Victoria

We are going to release Tempest new tag to declare the start of support
for stable/victoria. So that new tag use stable/victoria constraint in
the tox env.

For example, if anyone use Tempest 25.0.0 in future, let's say 1 year
later then tox env also should use the victoria constraint for
compatibility instead of master.

These need to be move back to master constraint, once release is done.

By using master constraint in tox for all the old tag is problem and we
faced the issue of constraint incompatibility due to that and we have to
workaround it all over the devstack, tempest role, grenade to set the
stable constraint via env var.

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

Change-Id: I1f8c788327b4a1a7f804cf01f8c22609e6646dd9

tox.ini

@@ -11,7 +11,7 @@ setenv =
     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 @@ usedevelop = True
 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 @@ commands =
 
 [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 @@ commands = {posargs}
 
 [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}/requirements.txt
   -r{toxinidir}/doc/requirements.txt
 commands =
@@ -348,7 +348,7 @@ paths =
 
 [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}/requirements.txt
   -r{toxinidir}/doc/requirements.txt
 commands =