Update tox.ini to work with tox 4

This change will allow this repo to pass zuul now
that this has merged:
https://review.opendev.org/c/zuul/zuul-jobs/+/866943

Tox 4 deprecated whitelist_externals.
Replace whitelist_externals with allowlist_externals

Due to unit test failures related to installing the
components, the Zuul file for this repo is pinned to
be less than tox 4.

Partial-Bug: #2000399

Signed-off-by: Al Bailey <al.bailey@windriver.com>
Change-Id: I906ebaa601170bd12183f1c983c3d5087014e696

.zuul.yaml

@@ -1,5 +1,7 @@
 ---
 - project:
+    vars:
+      ensure_tox_version: '<4'
     check:
       jobs:
         - openstack-tox-linters
@@ -37,7 +39,7 @@
     parent: tox
     description: |
       Run pylint test for k8sapp-oran-o2
-    nodeset: ubuntu-xenial
+    nodeset: ubuntu-bionic
     required-projects:
       - starlingx/config
       - starlingx/fault

python-k8sapp-oran-o2/k8sapp_oran_o2/tox.ini

@@ -19,7 +19,7 @@ distshare={toxworkdir}/.tox/distshare
 sitepackages = False
 
 # tox is silly... these need to be separated by a newline....
-whitelist_externals = bash
+allowlist_externals = bash
                       find
 
 install_command = pip install \

tox.ini

@@ -15,7 +15,7 @@ setenv =
 deps =
   -r{toxinidir}/requirements.txt
   -r{toxinidir}/test-requirements.txt
-whitelist_externals =
+allowlist_externals =
   bash
 
 passenv =