Fix tox4 error

Fixing tox4 error to remove the skipsdist=True and
add external command via allowlist_externals.

Change-Id: I55232b60e92f31891790ae0917fc5f582477cbed

tox.ini

@@ -1,7 +1,6 @@
 [tox]
 envlist = docs,linters
-minversion = 3.1.1
-skipsdist = True
+minversion = 3.18.0
 ignore_basepython_conflict = True
 
 [testenv]
@@ -26,7 +25,10 @@ commands =
 
 [testenv:linters]
 basepython = python3
-whitelist_externals = bash
+allowlist_externals =
+  bash
+  {toxinidir}/tools/check_projects_yaml_alphabetized.sh
+  {toxinidir}/tools/validate_repositories.py
 commands =
   osg-check-schema
   bash -c "find {toxinidir}        \
@@ -40,10 +42,14 @@ commands =
 
 [testenv:validate-legacy]
 envdir = {toxworkdir}/linters
+allowlist_externals =
+  {toxinidir}/tools/validate-legacy.py
 commands =
   {toxinidir}/tools/validate-legacy.py
 
 [testenv:validate_atcs]
+allowlist_externals =
+  {toxinidir}/tools/validate_atcs.py
 commands = {toxinidir}/tools/validate_atcs.py
 
 [testenv:pep8]
@@ -56,7 +62,7 @@ commands = {posargs}
 [testenv:docs]
 deps = -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
        -r{toxinidir}/doc/requirements.txt
-whitelist_externals =
+allowlist_externals =
   find
   rm
 commands =
@@ -68,4 +74,6 @@ commands =
 deps =
   requests
   prettytable
+allowlist_externals =
+  {toxinidir}/tools/check_review_status.py
 commands = {toxinidir}/tools/check_review_status.py