Fix tox v4 compatibility

Various changes to tox.ini to support v4

Change-Id: Iee2bceb78f5b03c559f23b99cde57fd598ce981a

tox.ini

@@ -1,7 +1,7 @@
 [tox]
 minversion = 3.18.0
-envlist = py38,pep8
-skipsdist = True
+envlist = py3,pep8
+#skipsdist = True
 # Automatic envs (pyXX) will only use the python version appropriate to that
 # env and ignore basepython inherited from [testenv] if we set
 # ignore_basepython_conflict.
@@ -10,19 +10,21 @@ ignore_basepython_conflict = True
 [testenv]
 usedevelop = True
 basepython = python3
-setenv = OS_STDOUT_CAPTURE=1
-         OS_STDERR_CAPTURE=1
-         OS_TEST_TIMEOUT=60
+setenv =
+    OS_STDOUT_CAPTURE=1
+    OS_STDERR_CAPTURE=1
+    OS_TEST_TIMEOUT=60
 deps =
-  -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
-  -r{toxinidir}/test-requirements.txt
-  -r{toxinidir}/requirements.txt
+    -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+    -r{toxinidir}/test-requirements.txt
+    -r{toxinidir}/requirements.txt
 commands = stestr run {posargs}
 allowlist_externals = stestr
 
 [testenv:fast8]
 # Use same environment directory as pep8 env to save space and install time
-setenv = VIRTUAL_ENV={envdir}
+setenv =
+  VIRTUAL_ENV={envdir}
 envdir = {toxworkdir}/pep8
 commands =
   {toxinidir}/tools/fast8.sh
@@ -74,14 +76,18 @@ commands =
 allowlist_externals = stestr
 
 [testenv:functional]
-setenv = OS_TEST_PATH=./openstackclient/tests/functional
-passenv = OS_*
+setenv = 
+    OS_TEST_PATH=./openstackclient/tests/functional
+passenv = 
+    OS_*
 commands =
     stestr run {posargs}
 
 [testenv:functional-tips]
-setenv = OS_TEST_PATH=./openstackclient/tests/functional
-passenv = OS_*
+setenv =
+    OS_TEST_PATH=./openstackclient/tests/functional
+passenv =
+    OS_*
 commands =
     python -m pip install -q -U -e "git+file://{toxinidir}/../cliff#egg=cliff"
     python -m pip install -q -U -e "git+file://{toxinidir}/../keystoneauth#egg=keystoneauth1"
@@ -108,7 +114,8 @@ commands =
     coverage xml -o cover/coverage.xml
 
 [testenv:debug]
-passenv = OS_*
+passenv =
+    OS_*
 commands =
     oslo_debug_helper -t openstackclient/tests {posargs}