Update tox.ini

whitelist_externals was replaced by allowlist_externals

Author: sebp

tox.ini

@@ -1,4 +1,5 @@
 [tox]
+min_version = 4.0
 envlist = sphinx
 skipsdist = True
 
@@ -14,7 +15,7 @@ commands =
     bash -c "grep -v '^\#' ./LINGUAS | tr '\n' ';' > .tmp-LINGUAS"
     xargs -a .tmp-LINGUAS -I '@' -d';' sphinx-build -D language='@' -E -W -b html ../source '../build/html/@'
     rm -f .tmp-LINGUAS
-whitelist_externals =
+allowlist_externals =
     /bin/bash
     /bin/rm
     /usr/bin/bash