Fix tox config to use poetry 1.2+

Signed-off-by: Aurélien Bompard <[email protected]>

tox.ini

@@ -6,8 +6,11 @@ isolated_build = true
 passenv = HOME
 skip_install = true
 whitelist_externals =
-    poetry
     rm
+# Use allowlist for poetry when poetry 1.2+ is more widespread
+#     poetry
+deps =
+    poetry>=1.2
 commands_pre =
     poetry install -E cli
 commands =
@@ -22,7 +25,7 @@ whitelist_externals =
 commands=
     mkdir -p _static
     rm -rf _build
-    sphinx-build -W -b html -d {envtmpdir}/doctrees .  _build/html
+    poetry run sphinx-build -W -b html -d {envtmpdir}/doctrees .  _build/html
 
 [testenv:lint]
 commands =
@@ -33,9 +36,6 @@ commands =
     poetry run black --check --diff {posargs:.}
 
 [testenv:licenses]
-# Make tox's poetry executable available for the run-liccheck script
-setenv =
-    PATH={env:PATH}{:}{env:TOX_WORK_DIR}{/}.tox{/}bin
 commands =
     poetry run {toxinidir}/devel/run-liccheck.sh