Fix tox 4 compatibility issues

Tox version 4 introduced changes that causes new failures in tox jobs.
This patch fixes these issues.

Change-Id: I76b01501a60941ff33caf9064a7771f60a1b891b

tox.ini

@@ -1,11 +1,10 @@
 [tox]
-envlist = py39,pep8
+envlist = py39,py310,pep8
 minversion = 2.3.2
 skipsdist = True
 
 [testenv]
 usedevelop = True
-basepython = python3
 setenv = VIRTUAL_ENV={envdir}
          NOSE_WITH_OPENSTACK=1
          NOSE_OPENSTACK_COLOR=1
@@ -45,7 +44,6 @@ setenv =
   INTEGRATION_TESTS=1
   SELENIUM_HEADLESS=1
   HORIZON_INTEGRATION_TESTS_CONFIG_FILE=neutron_fwaas_dashboard/test/integration/horizon.conf
-basepython = python3
 commands = {envpython} {toxinidir}/manage.py test neutron_fwaas_dashboard --tag integration {posargs}
 
 [testenv:docs]
@@ -54,7 +52,7 @@ commands =
 
 [testenv:pdf-docs]
 envdir = {toxworkdir}/docs
-whitelist_externals =
+allowlist_externals =
   make
 commands =
   sphinx-build -W -b latex doc/source doc/build/pdf